<html itemscope="" itemtype="http://schema.org/Organization" class=" js no-touch svg inlinesvg svgclippaths no-ie8compat" lang="en"><!--<![endif]--><head>

    <title>Grade 1 Elementary Math Games &amp; Problems | CK12</title>
    <meta property="og:site_name" itemprop="name" name="author" content="CK-12 Foundation">
    <meta property="fb:app_id" content="159884644067996">
    <meta itemprop="url" content="https://www.ck12.org">
    <meta itemprop="telephone" content="(650) 494-1302">
    <meta charset="utf-8">
    <!-- DNS Prefetching for domains -->
    <meta http-equiv="x-dns-prefetch-control" content="on">

        <link rel="dns-prefetch" href="//st1.ck12.org">

        <link rel="dns-prefetch" href="//st2.ck12.org">

        <link rel="dns-prefetch" href="//st3.ck12.org">

        <link rel="dns-prefetch" href="//img1.ck12.org">

        <link rel="dns-prefetch" href="//img2.ck12.org">

        <link rel="dns-prefetch" href="//img3.ck12.org">

        <link rel="dns-prefetch" href="//api-prod.ck12.org">






    <meta name="description" content="At ck12.org, we provide students and teachers alike with a variety of math games, problems and more.  We are a great resource for anyone wanting to learn.">





            <link rel="canonical" href="https://www.ck12.org/elementary-math/">
            <meta property="og:url" content="https://www.ck12.org/elementary-math/">



    <meta name="viewport" content="width=device-width">
    <meta name="google-site-verification" content="wHx0f-Udlfd7ZNYNrIXpJVpjjO8nSH5RE0jIX8V-jIM">
    <meta name="google-translate-customization" content="">
    <meta name="application-name" content="CK-12 Foundation">
    <meta name="msapplication-TileColor" content="#003300">
    <meta name="msapplication-TileImage" content="//img1.ck12.org/media/build-20181015164501/images/ck12-logo-livetile.png">

    <link rel="apple-touch-icon" href="//img1.ck12.org/media/build-20181015164501/images/ck12-logo-livetile-57x57.png">
    <link rel="apple-touch-icon" sizes="72x72" href="//img1.ck12.org/media/build-20181015164501/images/ck12-logo-livetile-72x72.png">
    <link rel="apple-touch-icon" sizes="114x114" href="//img3.ck12.org/media/build-20181015164501/images/ck12-logo-livetile-114x114.png">
    <link rel="shortcut icon" href="//img2.ck12.org/media/build-20181015164501/images/favicon.ico" type="image/x-icon">

	<link rel="search" type="application/opensearchdescription+xml" href="/opensearch.xml" title="CK-12 Foundation">



    <link rel="stylesheet" type="text/css" media="all" href="//st2.ck12.org/media/build-20181015164501/common/css/master.css">

	<link rel="stylesheet" type="text/css" media="all" href="//st3.ck12.org/media/build-20181015164501/elementarymath/css/elementarymath.css">
	<link rel="stylesheet" type="text/css" media="all" href="//st3.ck12.org/media/build-20181015164501/elementarymath/css/tutorial.css">

    <link rel="stylesheet" type="text/css" media="all" href="//st3.ck12.org/media/build-20181015164501/duplicateUsernames/css/content.css">



<meta name="header-mobile-page-title" content="Browse">





<header class="ff4-compt original-nav ">
	<div id="browserDetect" class="text-center hide" style="background-color:#FFEFAE;">
		<span id="browserVersion"></span>
		<a>Dismiss</a>
	</div>

	<a id="skip-navigation" href="#anchor-content"><img src="//img2.ck12.org/media/build-20181015164501/common/images/1x1.gif" width="1" height="1" alt="Skip Navigation"></a>
	<nav class="hide-small top-bar-section top-nav">
		<section class="top-bar row user-settings">




			<!--
            <div class='mid-header-banner'>
			</div>
            -->


			<ul class="right user-info">
				 <!-- If Signed in -->
					<li class="relative">
					<!-- Show Full Name -->

							<img src="https://lh6.googleusercontent.com/-PStava_PLBA/AAAAAAAAAAI/AAAAAAAAAAA/AAnnY7q4riUFo2XRUClnjGVIz3497xNz9g/mo/photo.jpg" width="28" height="28" class="image-user js_profile_image">

						<a id="top_nav_usermenu" data-dropdown="userdropmenu" class="user_name js_user_name">
							<span>Samih </span>
							<span class="drop-arrow hide-small">
						</span></a>
						<ul id="userdropmenu" class="f-dropdown usermenu">

							<li>
								<a id="top_usermenu_settings" href="https://www.ck12.org/account/settings" title="Settings">
									<span class="text-center menu-item-img icon-settings"></span>
									<span class="menu-item-title">Settings</span>
								</a>
							</li>
							<li>
								<a id="top_usermenu_signout" href="/account/signout/" title="Sign out">
									<span class="text-center menu-item-img icon-signout signout-dropdown"></span>
									<span class="menu-item-title">Sign Out</span>
								</a>
							</li>
						</ul>
					</li>
                    <li id="notification_nav" title="Notifications" class="relative">
						<a class="notification-nav-icon" data-dropdown="notification_container">
							<i class="icon-bell"></i><span class="drop-arrow hide-small"></span><span class="notification-count">1</span>
						</a>
						<ul id="notification_container" class="f-dropdown"></ul>
					</li>

                <li class="menu-help"><a id="top_nav_help" href="http://help.ck12.org" title="Help" target="new">Help</a></li>
                <li class="menu-donate">
					<a id="top_nav_donate" href="https://www.ck12info.org/about//donate/?source=ck12_top_nav" title="Donate" class="ga-track">
						<span>Donate</span>
						<i class="icon-heart"></i>
					</a>
				</li>
			</ul>
		</section>
	</nav>
	<nav class="top-bar row side-bar-expanded">
		<ul class="title-area text-center">
			<li class="name left">
				<a id="nav_logo" href="/" title="CK-12 Foundation Home" class="logo-img">
					<img src="//img2.ck12.org/media/build-20181015164501/common/images/logo_ck12.svg" alt="CK-12" itemprop="logo">
				</a>
			</li>
			<li class="pointer hidden hide-one back-icon left show-small"><i class="icon-arrow"></i></li>
			<li class="left ph-back hide"><i class="icon-arrow"></i></li>
			<li class="ellipsis page-title show-small">Browse</li>
			<li id="side-reveal-icon" class="pointer side-reveal menu-icon"><i class="icon-more"></i></li>
		</ul>

	<section class="relative top-bar-section" style="height: auto;">
			<ul id="top-bar-left-section" class="left top-navigation-list" data-magellan-expedition="relative" data-magellan-top-offset="1000000000000">


						<li class="show-small search-field-parent small">
							<div id="side_nav_search" class="left search-field-container-small">
								<input type="text" value="" placeholder="Search for free resources" class="search-small search-input ui-autocomplete-input" data-autocompleteclass="search" autocomplete="off"><span role="status" aria-live="polite" class="ui-helper-hidden-accessible"></span>
								<span id="loading-search-small" class="custom-loading-search-small right hide js-loading-icon">
									<img alt="loading" src="//img3.ck12.org/media/build-20181015164501/common/images/loading.gif">
								</span>
								<div class="left pointer search-button-small js-search-content">
									<i class="icon-search"></i>
								</div>
							</div>
						</li>


						<li id="notification_sidebar" class="show-small">
							<a id="nav_notifications" class="notification-nav-sidebar-icon" title="Notifications">
								<span class="menu-item-img">
									<i class="icon-bell"></i>
									<span class="notification-count">1</span>
								</span>
								<span class="menu-item-title">Notifications</span>
							</a>
						</li>


						<li class="original-nav-container">
							<ul>



								<li data-magellan-arrival="header_dashboard">
									<a id="nav_dashboard" href="/my/dashboard/" title="Dashboard" class="js-link">
										<span class="menu-item-img icon-dashboard2"></span>
										<span class="menu-item-title">Dashboard</span>
									</a>
								</li>
								<li data-magellan-arrival="header_groups">
									<a id="nav_groups" href="/my/groups/" title="Classes" class="js-link">
										<span class="menu-item-img icon-groups"></span>
										<span class="menu-item-title">Classes</span>
									</a>
								</li>
								<li class="hide-for-lti-context" data-magellan-arrival="header_library">
									<a id="nav_library" href="/my/library/" title="Library" class="js-link">
										<span class="menu-item-img icon-backpack"></span>
										<span class="menu-item-title">Library</span>
									</a>
								</li>

							<li class="forum-header-link" data-magellan-arrival="header_forums">
								<a id="nav_forums" href="/forums/" title="Cafe">
									<span class="menu-item-img icon-comments"></span>
									<span class="menu-item-title">Cafe</span>
								</a>
							</li>
							</ul>
						</li>


									<li class="browse-header-link hide-for-lti-context" data-magellan-arrival="header_browse">
										<a id="nav_browse" href="/browse/" title="Browse" class="js-link">
											<span class="menu-item-img icon-lightbulb2"></span>
											<span class="menu-item-title">Browse</span>
										</a>
									</li>



							<li id="search" class="show-for-medium hide-for-lti-context">
								<a id="nav_search_icon" title="Search">
									<span class="menu-item-img icon-search"></span>
									<span class="menu-item-title">Search</span>
								</a>
							</li>
							<li class="show-small">
								<a id="side_nav_help" href="http://help.ck12.org" title="Help">
									<span class="menu-item-img icon-help2"></span>
									<span class="menu-item-title">Help</span>
								</a>
							</li>
							<li class="show-small">
								<a id="side_nav_donate" href="https://www.ck12info.org/about//donate/?source=ck12_sidemenu" title="Donate">
									<span class="menu-item-img icon-heart"></span>
									<span class="menu-item-title">Donate</span>
								</a>
							</li>

				<li id="user-status" class="user link-container show-small">
					<ul>
					 <!-- If Signed in -->
						<li class="user-image-small">
							<a id="side_nav_username" class="cursor-default">


								<span class="relative menu-item-title">Samih </span>
							</a>
						</li>

						<li>
							<a id="side_nav_settings" href="/account/settings/" title="Settings">
								<span class="menu-item-img icon-settings"></span>
								<span class="menu-item-title">Settings</span>
							</a>
						</li>
						<li>
							<a id="side_nav_signout" href="/account/signout/" title="Sign out">
								<span class="menu-item-img icon-signout"></span>
								<span class="menu-item-title">Sign Out</span>
							</a>
						</li>

					</ul>
				</li>
			</ul>


			<ul class="right top-bar-right-section hide-small-important search-for-large hide-for-medium">
				<li class="search-field-parent large">
					<div id="nav_search" class="right search-field-container-large">
						<input type="text" value="" placeholder="What do you want to learn today?" class="search-large header-search search-input js-search-large ui-autocomplete-input" data-autocompleteclass="search" autocomplete="off"><span role="status" aria-live="polite" class="ui-helper-hidden-accessible"></span>
						<span id="loading-search" class="custom-loading-search right hide js-loading-icon">

						</span>
						<div class="left pointer search-button-large js-search-content">
							<i class="icon-search"></i>
						</div>
					</div>
				</li>
			</ul>

		</section></nav>
	<div id="searchBrowseContainer" class="container_12 relative">
		<ul id="searchContainer" class="row hide-for-large-up hide-for-small search-field-parent hide-important">
			<li class="search-wrapper left">
			 	<div id="searchComponent" class="large-10 small-12 columns">
			    	<div id="nav_search_medium" class="left search-field-container">
			        	<input type="text" class="search-field search-input js-search-large ui-autocomplete-input" value="" placeholder="What do you want to learn today?" data-autocompleteclass="search" autocomplete="off"><span role="status" aria-live="polite" class="ui-helper-hidden-accessible"></span>
						<span id="loading-search-medium" class="custom-loading-search-medium right hide js-loading-icon">

						</span>
			        	<div class="left pointer search-button js-search-content">
			          		<i class="icon-search"></i>
			        	</div>
			    	</div>
			    	<div id="searchClose" class="right pointer">
			        	<span class="close-icon"></span>
			    	</div>
		    	</div>
			</li>
		</ul>
	</div>
</header>
<div class="header-space hide-small-important"></div>



    <div id="softRegWrapper" class="grey-back"></div>







    <div id="content-container">

        	<a name="anchor-content"></a>

        	<div id="breadcrumbWrapper" class="row collapse breadcrumb-container hide"></div>

        	<div id="content-area" class="content-wrap row">


        		<!-- individual page contents go here -->

	<div id="page-disable" class="page-disable js-page-disable hide"></div>
 	<div id="loading-icon" class="loading-icon js-loading-icon hide">

	</div>
	<div id="elementarymath_contentwrap" class="row collapse"><div class="row collapse elementary-header hide-for-small">
	<h1>
		<a href="/browse/">Browse</a>
		<span>/</span>
		<a href="/math/">Math</a>
		<span class="branch-name" data-branch="elementary-math">/ Grade 1–5</span>
	</h1>
</div>
<div class="row collapse elementary-header show-for-small">
	<h1>
		<a href="/browse/">Browse</a>
		<span> / Grade 1–5</span>
	</h1><h1>
</h1></div>
<div class="row collapse relative">
	<div id="browse-grades" class="columns large-2 small-12 hide-for-small">
		<div class="row collapse grades-header bold">ELEMENTARY</div>
		<ul class="grades-wrapper" data-eid="MAT.EM">
			<li class="js-grade" data-grade="1">
				<div class="list-item">
					<a href="/json-grade/com/ustadmobile/lib/contentscrapers/ck12/index/classes.txt" class="selected">Grade 1</a>
				</div>
			</li>
		</ul>
	</div>
	<div class="columns large-2 small-12 show-for-small grades-wrapper-parent">
		<span class="row collapse grades-header left bold">GRADES:</span>
		<ul class="grades-wrapper left" data-eid="MAT.EM">
			<li class="js-grade text-center" data-grade="1">
				<div class="list-item">
					<a href="/json-grade/com/ustadmobile/lib/contentscrapers/ck12/index/classes.txt" class="selected">1</a>
				</div>
			</li>

		</ul>
	</div>
	<div class="large-9 small-12 columns">
		<div id="topic-container" class="row collapse"><div class="large-4 small-12 columns left">
	<div class="row collapse">
		<div class="large-8 small-12 columns">
			<div class="row collapse topic-wrapper text-center js-topic-wrapper" title="Addition and Subtraction to 20">
				<div class="row collapse image-wrapper">
					<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/add_sub_20.png">
				</div>
				<div class="topic-name">
					<a>Addition and Subtraction to 20</a>
				</div>
			</div>
		</div>
	</div>
</div>
<div class="large-4 small-12 columns left">
	<div class="row collapse">
		<div class="large-8 small-12 columns">
			<div class="row collapse topic-wrapper text-center js-topic-wrapper" title="Addition and Subtraction to 100">
				<div class="row collapse image-wrapper">
					<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/add_sub_100.png">
				</div>
				<div class="topic-name">
					<a>Addition and Subtraction to 100</a>
				</div>
			</div>
		</div>
	</div>
</div>
<div class="large-4 small-12 columns left">
	<div class="row collapse">
		<div class="large-8 small-12 columns">
			<div class="row collapse topic-wrapper text-center js-topic-wrapper" title="Time">
				<div class="row collapse image-wrapper">
					<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/time.png">
				</div>
				<div class="topic-name">
					<a>Time</a>
				</div>
			</div>
		</div>
	</div>
</div>
<div class="large-4 small-12 columns left">
	<div class="row collapse">
		<div class="large-8 small-12 columns">
			<div class="row collapse topic-wrapper text-center js-topic-wrapper" title="Measurement">
				<div class="row collapse image-wrapper">
					<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/measurement_yellow.png">
				</div>
				<div class="topic-name">
					<a>Measurement</a>
				</div>
			</div>
		</div>
	</div>
</div>
<div class="large-4 small-12 columns left">
	<div class="row collapse">
		<div class="large-8 small-12 columns">
			<div class="row collapse topic-wrapper text-center js-topic-wrapper" title="Geometry">
				<div class="row collapse image-wrapper">
					<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/geometry_red.png">
				</div>
				<div class="topic-name">
					<a>Geometry</a>
				</div>
			</div>
		</div>
	</div>
</div>
</div>
	</div>
</div>
</div>

	<div class="topic-details-wrapper hide" style="top: -916px;">
		<div id="owncontent" class="hide-for-small own-content" style="left: 0%;"><div class="topic-details-container js-topic-details-container left">
	<div class="topic-header" data-color="MAT_EM1_205">
		<div class="row collapse">
			<div class="columns large-10 large-offset-1">
				<span title="Addition and Subtraction to 20">Addition and Subtraction to 20</span>
				<div class="right pointer topic-close close-button js-topic-close">
					<i class="close-icon"></i>
				</div>
			</div>
		</div>
	</div>
	<div class="topic-details row collapse">
		<div class="columns large-10 large-offset-1 js-trackListContainer"><div class="row collapse concept-track-wrapper js-concept-track-wrapper">
	<div class="columns large-6 pointer concept-track-parent js-concept-track-parent" title="Addition and Subtraction facts to 20" data-eid="">
		<span class="concept-track-icon">
			<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/add_sub_20.svg">
		</span>
		<a class="relative concept-track">Addition and Subtraction facts to 20</a>
		<span class="for-place-only"></span>
	</div>
	<div class="columns large-6 concept-list-container js-concept-list-container">
		<ul>


				<li><a href="/json/com/ustadmobile/lib/contentscrapers/ck12/index/plix-list.txt">Add to 10 with Images</a></li>


		</ul>
	</div>
</div>
	</div>
</div>
		<div id="owncontentsmall" class="show-for-small own-content-small js-own-content-small"><div class="topic-details-wrapper-small js-topic-details-wrapper-small" data-topic-name="" data-color="MAT_ARI_103">
	<div class="topic-details-small row collapse">
		<div class="columns large-10 large-offset-1 trackListContainer-small js-trackListContainer-small"><div class="row collapse concept-track-wrapper js-concept-track-wrapper-small">
	<div class="columns large-6 pointer concept-track-parent js-concept-track-parent-small" title="Addition and Subtraction facts to 20" data-eid="">
		<span class="concept-track-icon">
			<img src="https://s3.amazonaws.com/concepts.ck12.org/preview/elementary-math/add_sub_20.svg">
		</span>
		<a class="ellipsis relative concept-track">Addition and Subtraction facts to 20</a>
		<span class="for-place-only"></span>
	</div>
	<div class="columns large-6 concept-list-container js-concept-list-container-small">
		<ul>





		</ul>
	</div>
</div>
		<div class="row collapse navigate-icon-wrapper js-navigate-icon-wrapper hide-for-small">
			<i class="icon-arrow3_left left js-left-navigate"></i>
			<i class="icon-arrow3_right right js-right-navigate"></i>
		</div>
	</div>

            <div class="row collapse" id="profilebuilder-content"></div>
            <div class="row collapse" id="ck12-license-container"></div>
            <div class="row collapse hide" id="notification_popup"></div>

     </div>

		<div class="footer-space hide-for-lti-context"></div>
<footer id="footer" class="ff4-compt hide-for-lti-context" style="">
	<div class="row collapse footer-wrapper">
	 <div class="row collapse footer-links-row">
		<div class="large-12 small-12 large-centered columns">
			<div class="row collapse footer-links-container">
				<div class="large-4 small-6 columns">
					<div class="row collapse footer-titles">ABOUT</div>
					<div class="row collapse footer-link-wrapper">
						<div class="large-6 small-12 columns medium-12">
							<ul>
								<li><a id="footer_mission" href="https://www.ck12info.org/about//mission/">Our Mission</a></li>
								<li><a id="footer_team" href="https://www.ck12info.org/about//team/">Meet the Team</a></li>
								<li><a id="footer_partners" href="https://www.ck12info.org/about//partners/">Partners</a></li>
								<li><a id="footer_pres" href="https://www.ck12info.org/about//press/">Press</a></li>
								<li><a id="footer_careers" href="https://www.ck12info.org/about//careers/">Careers</a></li>
								<li><a id="footer_security" href="https://www.ck12info.org/about//security/">Security</a></li>
							</ul>
						</div>
						<div class="large-6 small-12 columns medium-12">
							<ul>
								<li><a id="footer_community" href="https://www.ck12info.org/about//ck12-community/">Community</a></li>
								<li><a id="footer_success" href="https://www.ck12info.org/about//success-stories/">Success Stories</a></li>
								<li><a id="footer_blog" href="https://www.ck12.org/blog/">Blog</a></li>
								<li><a id="footer_overview" data-reveal-id="myModal">Overview</a></li>
								<li><a id="footer_usage_map" href="https://www.ck12.org/map/">CK-12 Usage Map</a></li>
								<li><a id="footer_testimonials" href="https://www.ck12.org/testimonials">Testimonials</a></li>
							</ul>
						</div>
					</div>
				</div>
				<div class="large-8 small-6 columns">
					<div class="row collapse">
						<div class="large-5 small-12 columns large-offset-1">
							<div class="row collapse footer-titles">SUPPORT</div>
							<div class="row collapse footer-link-wrapper">
								<ul>
									<li><a id="footer_jumpstart" href="https://www.ck12.org/certified">Certified Educator Program</a></li>
									<li><a id="footer_webinars" href="https://www.ck12info.org/about//ck12-webinars/">Webinars</a></li>
									<li><a id="footer_implementation" href="https://www.ck12info.org/about//overview/">CK-12 Resources</a></li>
									<li><a id="footer_pilot" href="https://www.ck12info.org/about//pilot-program/">Pilot Program</a></li>
									<li><a id="footer_help" href="https://ck12support.zendesk.com/hc/en-us">Help</a></li>
									<li><a id="footer_contact" href="https://www.ck12info.org/about//contact-us/">Contact Us</a></li>
								</ul>
							</div>
						</div>
						<div class="large-5 small-12 columns large-offset-1 by-ck12-wrapper">
							<div class="row collapse footer-titles">BY CK-12</div>
							<div class="row collapse footer-link-wrapper">
								<ul>
									<li><a id="footer_ccss" href="/flexbooks/browse/#math">Common Core Math</a></li>
									<li><a id="footer_flexbooks" href="https://www.ck12info.org/about//fbbrowse/">K-12 FlexBooks®</a></li>
									<li><a id="footer_colege_flexbooks" href="/college/">College FlexBooks®</a></li>
									<li><a id="footer_tools" href="https://www.ck12info.org/about//tools-and-apps/">Tools and Apps</a></li>
									<li><a id="footer_braingenie" href="https://braingenie.ck12.org/" class="notranslate">BRAINGENIE™</a></li>
								</ul>
							</div>
						</div>
					</div>
				</div>
			</div>
			<div class="footer-social-links-wrapper">
				<div class="large-4 small-12 columns small-centered translate-social-wrapper">
					<div id="google_translate_element" title="Select language"></div>
					<div class="right social_links">
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_googleplus" href="https://plus.google.com/+Ck12Org/" target="_blank" rel="noopener" class="icon-googleplus"></a></span>
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_facebook" href="https://www.facebook.com/CK12Foundation" target="_blank" rel="noopener" class="icon-facebook"></a></span>
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_twitter" href="https://twitter.com/CK12Foundation" target="_blank" rel="noopener" class="icon-twitter"></a></span>
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_linkedin" href="https://www.linkedin.com/company/75810" target="_blank" rel="noopener" class="icon-linkedin"></a></span>
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_pinterest" href="http://www.pinterest.com/ck12foundation/" target="_blank" rel="noopener" class="icon-pinterest-3"></a></span>
					  <span itemscope="" itemtype="http://schema.org/Organization"><a itemprop="sameAs" id="footer_email" class="footer-share-email-link icon-email"></a></span>
					</div>
					<div class="app-store-icons">
						<a id="apple-store-link" target="_blank" rel="noopener" href="https://itunes.apple.com/us/app/ck-12/id909343639?ls=1&amp;mt=8">
								</a>
						<a id="google-store-link" target="_blank" rel="noopener" href="https://play.google.com/store/apps/details?id=org.ck12.app.practice">
									</a>
					</div>
				</div>
			</div>
		</div>
	 </div>
	 <div class="row collapse footer-info-row">
	 	<div class="large-5 columns footer-version-info hide-for-small">
	 		<span>v2.8.2.20181011163612</span>
	 		<span class="year_version_separator">|</span>
	 		<span class="copy-right-year">© CK-12 Foundation 2018</span>
			<div><span>FlexBook® Platform</span></div>
	 	</div>
	 	<div class="large-7 small-12 columns footer-usage">
	 		<span><a id="footer_tou" href="https://www.ck12info.org/about//terms-of-use/" title="Terms of Use">Terms of Use</a></span>
	 		<span class="footer-separator">|</span>
	 		<span><a id="footer_privacy" href="https://www.ck12info.org/about//technology-2/privacy-policy/" title="Privacy">Privacy</a></span>
	 		<span class="footer-separator">|</span>
	 		<span><a id="footer_guidelines" href="https://www.ck12info.org/about//attribution-guidelines/" title="CK-12 Attribution Requirements">Attribution Guide</a></span>
	 		<span class="footer-separator">|</span>
	 		<span><a id="footer_license" href="http://creativecommons.org/licenses/by-nc/3.0/" title="CK-12 Foundation is licensed under Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)." target="new"><img class="footer_image" alt="Attribution-NonCommercial 3.0 Unported"></a></span>
	 	</div>
	 	<div class="large-5 small-12 columns footer-version-info-small show-for-small">
	 		<span>v2.8.2.20181011163612</span>
	 		<span class="year_version_separator">|</span>
	 		<span class="copy-right-year">© CK-12 Foundation 2018</span>
			<div><span>FlexBook® Platform</span></div>
	 	</div>
	 </div>
	</div>
</footer>

<!-- Tutorial Video -->
<div id="myModal" class="modal-uikit reveal-modal small">
	<div class="close close-reveal-modal button-close">+</div>
	<h4>CK-12 Overview</h4>
	<div class="flex-video"></div>
</div>


<div class="hide">


	<!-- All the divs inside this div will be hidden and are used for showing dialogs and messages -->
	<div id="loading_div">
		Please wait...
	</div>


	<div id="js_signindialog" data-url="https://www.ck12.org/auth/signin?popup=true&amp;requestor=https%3A//www.ck12.org/elementary-math/&amp;returnTo=https%3A//www.ck12.org/account/federated/authorized/popup/" data-auth-no-popup-url="https://www.ck12.org/auth/signin?&amp;requestor=https%3A//www.ck12.org/elementary-math/&amp;returnTo=https%3A//www.ck12.org/elementary-math/">
		<div class="action"><a id="signin_close" href="#" alt="Close Sign In " title="Close Sign In"></a></div>
	</div>

	<div id="js_dialog_basic">
	<!-- used for simple OK/Cancel or Alert type dialogs. -->
	<div class="dialog_msg"></div>
	<div class="dialog_loading hide">Please wait...img width="43" height="11"></div>
	</div>

</div>




<script type="text/javascript" ></script>
<script ></script>

<script ></script>






<script data-main="//st3.ck12.org/media/build-20181015164501/main" ></script>


<script language="javascript" type="text/javascript">

    function getCookie(c_name){
        var i,x,y,ARRcookies=document.cookie.split(";");
        for (i=0;i<ARRcookies.length;i++){
          x=ARRcookies[i].substr(0,ARRcookies[i].indexOf("="));
          y=ARRcookies[i].substr(ARRcookies[i].indexOf("=")+1);
          x=x.replace(/^\s+|\s+$/g,"");
          if (x==c_name) {
            return unescape(y);
          }
        }
    }

    function getRandomString(length) {
        var chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', value = '';
        for (var i = length; i > 0; --i) {
            value += chars[Math.round(Math.random() * (chars.length - 1))];
        }
        return value;
    }

    // login user role is c.user.role for guest role is in cookies.
    var flxweb_role;
    var flxweb_roles = [];
    var isEditAllowed = false;
    var webroot_url = 'https://www.ck12.org/';
    var editprofile_url = 'https://www.ck12.org/auth/profile?returnTo=https%3A%2F%2Fwww.ck12.org%2Faccount%2Fsettings%2F&appHome=https%3A%2F%2Fwww.ck12.org%2F';
    var adaptive_practice_launch_date = '';


        flxweb_role = getCookie('flxweb_role');
        flxweb_roles.push(flxweb_role);
        window.ck12_signed_in = false;


    dexterjs.set("config", {
        clientID: 24839961,
        trackPageTime: false
    });

    if (window.lmsContext === 'lti-app'){
        // Add in appID and provider for ADS
        // when in lti context
        try {
            appInfo = JSON.parse(sessionStorage.getItem('ltiAppInfo'));
	    var mixins = { appID: appInfo.appID,
	          lmsProvider: appInfo.provider,
		  appContext: appInfo.lms_name
	    }
            dexterjs.set('config', {mixins:mixins});
       } catch(e) {
            console.error("Error adding ADS mixins for lti: "+ plix-listString(e));
       }
    }
    _ck12 = dexterjs;

    function startPageTimer() {
        window.adsPageStartTime = new Date().getTime();
    }

    function adsLogPageTime() {
        var endTime = new Date().getTime();
        var timeOnPage = Math.round((endTime - window.adsPageStartTime)/1000);
        //pageType, URL, duration (in seconds)
        var payload = {
            'URL' : document.location.href,
            'duration': timeOnPage
        };
        if(window.adsPage) {
            payload['pageType'] = window.adsPage;
        } else if (window.pageType) {
            payload['pageType'] = window.pageType;
        }

        if (window.adsSubject) {
            payload['subject'] = window.adsSubject;
        }
        if (window.adsBranch) {
            payload['branch'] = window.adsBranch;
        }
        if (window.adsContextEid) {
            payload['context_eid'] = window.adsContextEid;
        }
        if (window.artifactID) {
            payload['artifactID'] = window.artifactID;
        }

        _ck12.logEvent('FBS_TIMESPENT', payload);
     }

    function adsOnload() {
        if (window.ck12_signed_in) {
            createCookieActiveUser();
        }
        startPageTimer();
    }

    function adsOnBeforeUnload() {
        adsLogPageTime();
    }

    function createCookieActiveUser(){
        var value;
        var now = new Date();
        var time = now.getTime();
        var expireTime = time + 1000*3600;
        now.setTime(expireTime);
        var activeCookie = getCookie('flxweb_user_active');
        if(activeCookie){
            value = activeCookie;
        }else{
            value = getRandomString(25);
            payload = {
                'sessionID': value
            };
            _ck12.logEvent('FBS_ACTIVE_USER', payload);
        }
        document.cookie =
            'flxweb_user_active=' + value +
            '; expires=' + now.toUTCString() +
            '; path=/';
    }

    function addEvent(obj, evt,fn,useCapture){
        if(obj.addEventListener){
            obj.addEventListener(evt,fn,useCapture);
            return true;
        }else if(obj.attachEvent){
            var r=obj.attachEvent('on'+evt,fn);
            return r;
        }else this['on'+evt]=fn;
    }

    addEvent(window, "load", adsOnload);
    var existingOnBeforeUnloadHandler = window.onbeforeunload;

    function handleExistingBeforeUnload() {
        var returnValue;
        if (existingOnBeforeUnloadHandler){
            returnValue = existingOnBeforeUnloadHandler(event);
        }
        adsOnBeforeUnload();
        if (returnValue) {
          return returnValue;
        }
    }
    addEvent(window, "beforeunload", handleExistingBeforeUnload);

<!--Browser Cookie detection start -->
var cookieEnabled = (navigator.cookieEnabled) ? true : false;
if (typeof navigator.cookieEnabled == "undefined" && !cookieEnabled)
{
    var cookieName = "CK12-Cookie-Test";
    document.cookie= cookieName;
    cookieEnabled = (document.cookie.indexOf(cookieName) != -1) ? true : false;
    if (cookieEnabled){
        document.cookie = cookieName + "=; expires=Thu, 01 Jan 1970 00:00:01 GMT;";
    }
}
if (!cookieEnabled){
    cookieBar('block');
}

function cookieBar(displayValue){
    var cookies_msg_container = document.getElementById("nocookies");
    if (cookies_msg_container != null){
        cookies_msg_container.style.display = displayValue;
    }
}

</script>
<!--Browser Cookie detection end -->

<script type="text/javascript">
require(['main'], function () {
    require(['elementarymath/controllers/elementarymath', 'common/utils/user'], function (elementary, User) {
        elementary.init(document.getElementById('elementarymath_contentwrap'), document.getElementById('owncontent'), document.getElementById('owncontentsmall'));

        /*function initGCPromoBanner() {
            var container;
            container = document.getElementById('google-classroom-banner')
            GCPromoBanner.initGCPromoBanner(container, true);
            window.mixpanel && window.mixpanel.track('GCPromo_Banner_Shown');
            try {
                window.dexterjs && window.dexterjs.logEvent('FBS_USER_ACTION', {'desc':'GCPromo_Banner_Shown'});
            } catch(error){
                console.log("Could not log ADS event GCPromo_Banner_Shown: "+ error);
            }
        }

        $(document).ready(function(){
            User.getUser().done(function(userData){
                if (userData.isLoggedIn(false)) {
                    if (!userData.is_student()){
                        initGCPromoBanner();
                    }
                } else {
                    initGCPromoBanner();
                }
            });
        });*/

     });
});
</script>


<script>
    if(window.lmsContext === 'lti-app'){
       loadingCheck();
    }
</script>


 <noscript>
   <div style="position:fixed; top:0;left:0;right:0;margin:auto; z-index:9999;">
      <div class="row collapsed" style="text-align:center;background-color:#FFFF99;padding:5px 5px 5px 5px; border:2px solid #999;font-size:16px;text-shadow:none;color:#000000;">
          <div>To use this website, please enable javascript in your browser. <a style="text-shadow: none;color:#0000FF;text-decoration:underline;" href="/nojavascript/">Learn more</a></div>
      </div>
  </div>
</noscript>



<!-- START cookie disabled message -->
<div id="nocookies" style="text-align:center; top: 0px; width:100%; position:absolute;	z-index:9999; display:none;">
    <div id="nocookies_inner" style="margin:0 auto; height:16px;	width:800px; background-color: #FFFF99;	padding:4px 10px 10px 10px; border:3px solid #999; font-size: 16px; text-shadow: none; color: #000000;">
        <div class="cookiemsg" style="float:left;">Oops, looks like cookies are disabled on your browser. Click <a style=" text-shadow: none;color: #0000FF;" href="/nocookies/">here</a> to see how to enable them.</div>
        <div class="cookies_close" style="float:right;"><a style="text-decoration:none;color: #000000;" href="javascript:void(0);" onclick="cookieBar('none');">X</a></div>
    </div>
</div>
<!-- END cookie disabled message -->


<!--
	###############################
	#  FLXWEB DEBUG INFORMATION
	###############################
	flxweb_node_name = flxweb2
	processing_time  = 0.3498
-->

<ul class="ui-autocomplete ui-front ui-menu ui-widget ui-widget-content ui-corner-all" id="ui-id-1" tabindex="0" style="display: none;"></ul><ul class="ui-autocomplete ui-front ui-menu ui-widget ui-widget-content ui-corner-all" id="ui-id-2" tabindex="0" style="display: none;"></ul><ul class="ui-autocomplete ui-front ui-menu ui-widget ui-widget-content ui-corner-all" id="ui-id-3" tabindex="0" style="display: none;"></ul></body></html>