You must be 13 years old to use this website. If you are not yet 13 years old, please visit us on your 13th birthday!

The purpose and mission of this site

The goal of the website ("the website") and its related projects are to improve the quality of education while lowering expenses. This is largely accomplished by providing, distributing, and organizing educational information, materials, and services.

You are legally responsible for anything You submit to this website, and content submitted or posted is licensed to be used by OpenIntro

You are legally responsible and liable for any information you submit. You agree to not submit materials or link to materials that are unlawful for individuals of any age in any state or district of the United States of America to view. You agree not to in any way encourage, endorse, or promote behavior or postings that would be unlawful or violate these terms of use.

You acknowledge and accept that we may examine materials that you post to the website, even if they are in private courses and have not been flagged by site users. For example, we may examine a teacher account if the teacher has an unusual number of uploads. You agree to allow OpenIntro to remove any of your materials, including course materials, if those materials violate a copyright, license, or OpenIntro believes the material to be inappropriate. You also agree to allow OpenIntro to delete any materials that are not used for more than 12 months. (We will often, but not always, attempt to contact the user in such cases.)

Any materials (also called products) you submit or post on this website are licensed to OpenIntro under both a Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license and a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0) license. You understand that if we use any of your submitted or posted materials, we will provide attribution in one of the following two ways. Option 1: We will list you as an original creator or contributor to the product while also providing similar attribution to any other individuals or entities that contributed to the released product. Option 2: We will make clear on a product summary page that you are the original creator of some or all of the materials while providing similar attribution to other contributors. If you submit or post any materials to the website, you agree that either attribution option listed above is sufficient to satisfy the attribution component of the licenses listed above. You retain the copyright to your original content and so may release it to others in any way you deem appropriate, and you may use your materials in pursuit of profit, as is your right as the copyright owner.

You agree to allow Openintro to host materials on the website that you submit or post to the website indefinitely. You also agree that by hosting your materials (without substantive changes), OpenIntro is not obligated to release the material under a Creative Commons license. This paragraph is saying that your materials are not automatically released under one of the two Creative Commons licenses listed in the preceding paragraph just because the materials are hosted on the website. If OpenIntro releases the materials in a modified way or through any other medium, then we agree to release the file under one or both of the licenses listed above. No aspect of this paragraph affects the copyright ownership of your original materials or your ability to release original materials under any license you desire.

Users viewing or obtaining materials from a course on the website understand all of these materials are copyrighted and are not being released by OpenIntro or the course instructor to site users under any license unless otherwise stated.

Accuracy, timeliness, availability of this site and its contents are not guaranteed

Occasionally we will make an error, mis-statement, or mistake. Examples, exercises, and other information may not represent real-world information. By using this site, you agree not to hold OpenIntro liable for information, actions, inaccuracies, or any other component of the website or project.

Sometimes this site will not be available. In some instances we may notify users either by email or by a message on the website that there will be scheduled maintenance. Sometimes we will not provide this information ahead of time or the email or message delivery will fail. You agree not to hold OpenIntro liable if this website or any of its resources are not available to you at any time or if there is an error made by OpenIntro.

You acknowledge and accept that not all content may be entirely accurate and that it is your responsibility to seek out and verify details when appropriate (e.g. for a job posting, you should verify application deadlines using the original posting).

The site and all of its contents are copyrighted, however, some of these materials are released under Creative Commons licenses

All materials and text on this site is copyrighted by OpenIntro, the site users, or the site contributors. Materials may be used, redistributed, shared, and modified only when specified and under the corresponding license. By using this site, you agree to abide by these licenses and any copyright and license laws.

You agree to not use HTML frames in conjunction with our website and to not call images or files from our server to an alternative web domain.

You agree to allow OpenIntro to remove information, content, questions, or other materials for any reason (e.g. copyright infringement or offensive material).

Data management, retention, and sharing

Users agree to allow OpenIntro to use tracking files known as "cookies".

Below are samples of information that OpenIntro collects and may retain and use indefinitely:

  • Quiz performance data
  • User account information
  • Any content submitted through the website
  • Actions or activity of users visiting the site

We collect this information because it allows us to improve the website and our resources. For instance, we can assess the quality of different pieces of our site by assessing user interactions. By using this site, you agree to participate in this data collection.

You agree to allow OpenIntro to share your personal information when you elect for it to be shared, e.g. when you enroll in a course. By using this website, you also agree to allow OpenIntro to share anonymized data (i.e. names, email addresses, and passwords removed) with the public or with other groups. Data-sharing exceptions related to malicious activity are identified below. You also acknowledge that OpenIntro may grant access to law enforcement officials if it is deemed necessary by OpenIntro or OpenIntro is instructed to do so by a court. Additionally, if you impersonate any individual or entity, you agree that we may share any information you have provided with the person or entity you have impersonated. For example, if you are applying for a teacher account, contact staff at any schools to confirm your teaching status during our review of your application and in that process share your name and email address. If we believe that your application contains false information, e.g. as part of a teacher application by a student, you understand and agree that we may share information about your account (including your teacher application) to relevant school(s) should they ask for additional information. For this reason, we suggest students not apply for teacher accounts unless they serve in a formal instructor role (your application would be rejected anyways, so don't waste your time or ours).

If a verified teacher invites you and you are or become registered on OpenIntro, you accept that the verified teacher who invited you will be notified that you registered and / or will be shown in some other view that you joined Information that will be shared includes your email (the verified teacher must have already had your email to invite you), your first and last name, and the date you registered, and if you have confirmed your email address. These persons may also reach out to you. Please note that Verified Teachers are considered our most trusted set of website visitors, since they have either gone through a verification process or were invited to the site by another verified teacher.

Courses, discussion boards, and public forums

Users who have registered for a course in a subject agree for their name, email address, student ID numbers, performance data (e.g. quiz scores and individual question data), and other information to be shared with the course’s manager (course creator) and any course teaching assistants or course managers who review course content or assist in managing the course. Users agree that if they create a thread or post a message to a discussion board or public forum, their user ID or name may be shown with that comment.

Users who are registering for a course acknowledge that OpenIntro cannot generally verify the identity of an instructor, even if the instructor has undergone simple verification through the website, so it is a choice of the user to decide whether the instructor truly is the person the user believes him or her to be. This choice is not to be taken lightly.

If you become a course manager (also called instructor or teacher, which is anyone running any course on the website), you agree to allow OpenIntro to share your name, your email address, the course's name, and also whether or not you are a Verified Teacher to any user who has the Course ID and Access Code for your course.

Accounts on

By registering on, you agree to receive occasional emails; we aim for 3 or fewer general emails per year, though you may receive other account-specfic emails (e.g. if you reset your password, you will receive an email). If you would like to opt out of promotional emails, you may do so by emailing our admin account: see the contact page for the admin email address.

We reserve the right to cancel an account, retract a teacher's verified or whitelisted status, cancel a textbook request, or take other actions we deem to be appropriate regarding user accounts on OpenIntro.

Malicious users and vandalism

We monitor data collected on this website to try to improve the website and its contents. Sometimes this may lead us to find a user that is acting maliciously (e.g. we see an outlier that we investigate further). If malicious behavior is identified, names, email addresses, and all other information that we deem necessary to describe malicious behavior or identify a malicious user may be shared with law enforcement or other authorities and the manager of any courses that the offending user has enrolled in. Please note that course managers may share information about malicious activity to appropriate academic officials, which may affect the offending user's academic standing, employment status, and reputation.

You acknowledge and accept that we will record some of your actions on this website, and that this information may be used in court. We take malicious behavior and vandalism on the site very seriously. Below are a few examples of what is considered malicious behavior:

  • registering multiple accounts and using more than one of those accounts to rate content;
  • intentionally flagging items inaccurately, e.g. flagging a question as copyrighted content when it is in fact original user content;
  • attempts at SQL injection.

This list is not comprehensive. Users agree to allow OpenIntro to recognize patterns of malicious behavior. Malicious behavior and vandalism is any behavior OpenIntro believes to be damaging to the website’s integrity, usability, or which may negatively affect users on the site. We may (or may not, depending on the severity of the actions) issue a warning to the user before reaching out to law enforcement or course instructors.

To be forward, we built this site because we support open and low cost education, not because we want to police user activity. These terms are for our protection so that we can continue providing contributions to the education community. We hope you are also enthusiastic about and will join us in fulfilling this mission.

Changes to these terms may occur

These terms of use may change. The latest terms of use will always apply to all users. By using OpenIntro, you agree to abide by these changes. If OpenIntro sends an email to notify you of a change in terms, which it will not typically do, you agree not to hold OpenIntro liable if you do not receive an email with information about a change in these terms or the privacy policy. With this in mind, we make a concerted effort to notify users of major overhauls of these terms and privacy policy. If you would like to remain up-to-date at all times on the terms of use, we advise you to visit this page at the start of each visit to the OpenIntro website.


OpenIntro is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to

Voiding part of these terms does not void all the terms

If part of these terms are voided due to a conflict with any law or for any other reason, the rest of the terms of use will remain valid and continue to apply to the site users. If part of these terms are not valid in one or more states, then those terms will remain in effect for all other states where they are otherwise valid and it will not affect any other part of the terms.

Terms of Use License

The text of these Terms of Use are released under a Creative Commons Attribution-ShareAlike 3.0 license. However, usage of the Terms of Use comes with absolutely no warranty for guarantee.