Giving us credit when you use our content and technology is important for legal reasons, but also supports our ability to make great educational experiences available to students around the world at no cost. Our CK-12 Curriculum Materials License welcomes you to use our content in accordance with that license.
If you display CK-12 content on your website, we require that you do the following on all pages of your website that contain CK-12 content:
STEP 1
Add the CK-12 Attribution Badge
LICENSED UNDER
You can use the following HTML code to render the above CK-12 attribution badge:
<div style="border: 1px solid #ccc;padding: 10px 12px;border-radius: 7px;width: 220px;"><div style="width: 88px;float: left;"><a href="https://www.ck12.org/" target="_blank"><img
Search Engine Crawling & Indexing of Content
To make sure internet search engines, like Google, understand that CK-12 is the source of the content, we require that you follow ONE of the options mentioned below:
OPTION 1:
Block search engines from crawling CK-12 content on your website.
Add the noindex rule on all pages of your website that contain CK-12 content, so as to block search engines from crawling and indexing CK-12 content displayed on your website.
There are two ways for adding the noindex rule to your website pages.
1. Add a noindex rule using a meta tag on each page. To prevent most search engine web crawlers from indexing a page on your site, place the following meta tag into the head section of your page:
2. Add a noindex rule using an HTTP response header. Instead of a meta tag, you can also return an X-Robots-Tag header with a value of either noindex or none in your response. Here’s an example of an HTTP response with an X-Robots-Tag instructing crawlers not to index a page:
OPTION 2:
Add canonical tags pointing to content on the CK-12 website.
For each page on your website that contains CK-12 content, add the HTML canonical link tag in the head section of your website HTML page. The URL in the href attribute of this canonical tag should be the complete absolute URL of that content on the ck12.org website.
As an example, if a page on your website uses content from the CK-12 cell nucleus page, then you are required to add the following HTML canonical link tag in the <head> section of your website page.
lesson/cell-nucleus-bio” />
You may also choose to set the canonical using the HTTP headers.
STEP 3
Link Back to the CK-12 Source
Add a link back to the source page on the CK-12 website. As an example, if a page on your website uses content from the CK-12 cell nucleus page, then you are required to add the following HTML link on your page:
Source: https://flexbooks.ck12.org/cbook/ck-12-biology-flexbook-2.0/section/2.6/primary/lesson/cell-nucleus-bio