CK-12's AI Tutor, Flexi
Product by CK-12 Foundation
Facts checked: Not yet checked
Our take (not a Learning Standard rating). This label applies to learning-science judgments throughout this overview.
Our take (not a Learning Standard rating)
While The Learning Standard has not yet fully evaluated Flexi, its integration of step-by-step guidance aligns with strong pedagogical practices for STEM subjects. It provides targeted hints rather than immediate answers, encouraging active retrieval practice, though its text-heavy interface requires strong reading comprehension skills from your child.
Pros
- Utilizes worked examples to break down complex math and science problems into manageable steps.
- Employs scaffolding by offering hints instead of direct answers to encourage active problem-solving.
- Integrates directly with digital textbooks to ensure AI assistance remains aligned with the core curriculum.
- Generates interest-based analogies to connect abstract scientific concepts to a student's prior knowledge.
Cons
- Requires strong reading comprehension and typing skills to navigate the conversational AI interface effectively.
- Lacks voice-to-text or handwriting recognition for inputting complex mathematical notation.
- Carries the standard risk of AI chatbots occasionally generating inaccurate explanations or hallucinating facts.
What Do We Know About CK-12's AI Tutor, Flexi?
CK-12's AI Tutor, Flexi, is an effective supplementary tool for middle and high school students who need interactive support in math and science. Your child interacts with a chatbot that provides immediate, targeted feedback when they get stuck on a specific concept. Unlike search engines that simply provide answers, Flexi uses pedagogical scaffolding. It prompts your child with hints and breaks complex calculations down into worked examples. This forces your child to engage in retrieval practice rather than passively copying a solution. Because Flexi relies on text-based conversation, your child must possess strong reading and typing skills to benefit from it. It works best when paired with CK-12's digital textbooks, known as FlexBooks, as the AI can directly reference the reading material. You should monitor your child's usage, as large language models occasionally provide inaccurate analogies or misinterpret poorly phrased questions. However, for a free resource, it offers a robust method for your child to test their understanding and receive immediate corrective feedback without waiting for a teacher.
How Does CK-12's AI Tutor, Flexi Work?
Flexi utilizes personalized, mastery-based learning by integrating a conversational AI assistant directly into a digital STEM curriculum. When a student encounters a difficult concept in a CK-12 FlexBook, they can ask Flexi a question via text input. The system responds using natural language processing to assess the student's current understanding. If a student inputs a math problem, Flexi does not output the final number. Instead, it generates a step-by-step worked example, requiring the student to complete intermediate steps. If the student struggles to understand a scientific definition, the AI generates custom analogies based on user interests, effectively linking new information to the student's prior knowledge schema. The platform also includes a translation feature, allowing English language learners to process complex academic vocabulary in their native language while interacting with the core curriculum. Teachers and parents receive backend data on which questions students ask most frequently, highlighting gaps in foundational knowledge.
Strengths and tradeoffs of CK-12's AI Tutor, Flexi
Flexi's biggest strength is its use of scaffolding to prevent students from shortcutting the learning process, while its biggest weakness is the cognitive load required to navigate a text-heavy chatbot interface. Strengths: Flexi excels at providing immediate corrective feedback, a crucial component of mastery learning. When students make an error, the AI intervenes with hints rather than just marking the answer wrong, which promotes productive struggle. Furthermore, the platform's ability to generate custom analogies helps build schema construction. By relating physics principles to sports or biology to video games, it anchors abstract concepts into familiar contexts. Weaknesses: The reliance on a conversational interface presents a high barrier for entry. Younger students or those with reading difficulties may experience cognitive overload when trying to parse long text responses while simultaneously processing difficult math or science content. Additionally, like all AI tutors, Flexi is susceptible to occasional errors or misinterpretations of student intent. The lack of voice-to-text limits its accessibility for early elementary users or students trying to input complex mathematical notation.
Who Might Benefit From CK-12's AI Tutor, Flexi?
Best for middle and high school students who need on-demand homework help in STEM subjects and possess strong reading comprehension skills. Flexi is an excellent resource for independent learners working through CK-12's science and math curriculum. Because it relies heavily on a text-based conversational interface, it is less suited for early elementary students. It is highly effective for students who benefit from step-by-step scaffolding and personalized analogies, serving as a reliable secondary support system when a human teacher or parent is unavailable to explain complex concepts.
Data Transparency
Does Not Meet Data Transparency Standard
CK-12's AI Tutor, Flexi does not meet our data transparency standard. Its privacy policy does not document basic protections, including a statement that it does not sell data, a commitment against targeted advertising and a COPPA or FERPA commitment.
16 of 35 checks passed
Evaluated September 2026
Privacy Policy →Level 1 · Basic protections
Does not sell data or target ads at students, limits sharing, and lets parents see and delete their child's data.
Not documented: a statement that it does not sell data, a commitment against targeted advertising, a COPPA or FERPA commitment
Level 2 · Parent control (meets the standard)
Families can get their data out, know who processes it, and know how long it is kept.
Not documented: a data retention timeline, self-service deletion
Level 3 · Direct data access
Families or schools can pull their own data through an API, in a stated format.
Not documented: an API for retrieving their own data, a named export format
View all 35 checks
Parent Access5/8
Does the policy mention parents specifically?
“Younger visitors should always check with their parents or guardians before entering information online.”
Can parents view their child's data?
“Review the personal information we maintain about your child;”
Can parents modify their child's data?
The policy lets parents review, delete, or stop the use of their child's data, but it does not give parents a right to modify it.
Can parents delete their child's account?
“Direct us to delete the personal information we maintain about your child; and”
Is there a dedicated Children's Privacy section?
“**2\. CHILDREN’S PRIVACY**”
Does it reference COPPA compliance?
The policy does not mention COPPA.
Does it reference FERPA compliance?
The policy mentions "student records" but does not name FERPA.
Is parental consent required for child accounts?
“If we become aware that a child user wants to access the Platform, we will take steps to obtain consent from their parent or guardian.”
Data Portability3/5
Can users access their personal data?
“If you are registered with us, you may log into your account to access and correct your account information.”
Can users download/export their data?
“You can ask us for a copy of your personal information and can ask for a copy of personal information to be provided in machine readable form.”
Is there a self-service data access tool?
“If you are registered with us, you may log into your account to access and correct your account information.”
Is a specific data format mentioned for export?
The policy only says "machine readable form" and names no specific format.
Is there an API for data access?
The policy does not mention an API for accessing data.
Data Minimization1/6
Is data collection itemized?
“If you are a student or teacher, we may collect information such as your name, telephone number, email address, mailing address, birth date, profile photo, demographic data, and account login information (i.e., username and password).”
Can the app be used without a real name?
The policy says it collects student names.
Can the app be used without an email?
The policy says it collects student email addresses.
Does it state collection is limited to what is necessary?
The policy does not say that collection is generally limited to what is necessary.
Is IP address anonymized or truncated?
The policy says it collects IP addresses and does not mention anonymizing them.
Is location tracking explicitly excluded?
The policy says it collects device city information and does not rule out location tracking.
Third-Party Protection5/7
Does it explicitly state no selling of data?
The policy does not say that CK-12 does not sell personal information.
Are third-party providers named?
“For example, we use Google Analytics to collect and analyze information about our users’ demographics and interests in order to measure and improve the Platform.”
Are providers contractually restricted?
“We take steps to prohibit our service providers from using your personal information for purposes outside of providing services to us.”
No-targeted-advertising commitment?
The policy makes no commitment against targeted advertising and says it measures ads it places on third-party websites.
Is AI/ML data sharing addressed?
“We may also aggregate or deidentify information about users of our Platform to train AI models, understand usage trends, and gather opinions, comments, and suggestions about our Platform.”
Child-specific sharing restriction?
“To protect the privacy of children (see the definition above), certain functionality associated with a child’s account will be disabled to ensure that the child’s profile information (including profile photo) will not be visible to others on our Platform.”
Cookies/tracking limited or opt-out?
“For more information about Google Analytics and how to opt out, please visit [https://tools.google.com/dlpage/gaoptout/](https://tools.google.com/dlpage/gaoptout/).”
Deletion & Retention2/5
Can users delete their account?
“You may request to cancel your membership and have your account removed from our Platform. Please make all cancellation requests via email to [support@ck12.org](mailto:support@ck12.org).”
Self-service deletion mechanism?
The policy says account deletion is requested by email, not done through a self-service tool.
Specific data retention timeline?
The policy keeps data as long as an account exists or as necessary, with no specific timeline.
Auto-deletion of inactive accounts?
The policy does not address automatic deletion of inactive accounts.
Post-deletion handling described?
“We may anonymize your personal information after you have deactivated or deleted your account so that we can use this anonymized information for our internal business purposes.”
Advertising0/4
Advertising model explicitly disclosed?
The policy does not describe advertising in the product; it mentions only ads CK-12 places on third-party websites.
Free from third-party advertisements?
The policy does not say the product is free of third-party ads.
Children excluded from ad targeting?
The policy does not address excluding children from ad targeting.
Ad-free option available?
The policy does not say the product has no ads or offer an ad-free option.
What This Means
The policy review did not meet our data transparency standard. The checks above show the documented findings and unknowns. A missing statement does not establish how the app handles data in practice.
About this evaluation: Based on automated analysis of Privacy Policy against 35 policy-disclosure questions, including questions adapted from the Common Sense Privacy Program's published evaluation questions. TLS is not affiliated with Common Sense Media, and this is not a Common Sense rating. Quoted text is copied from the policy; unquoted notes are our summary. Results describe what the policy documents, not the company's actual practices. Privacy policies can change: this review reflects the version we analyzed and does not determine legal compliance.
Sources and review method
TLS combines product information and editorial analysis to explain how CK-12's AI Tutor, Flexi works, its tradeoffs, and the questions to ask before choosing it. Product features, an instructional rationale and evidence of learning outcomes are different kinds of information.
Formal Learning Standard assessment: not yet completed. Data Transparency findings are reported separately and do not establish learning effectiveness. Read our methodology.
Frequently Asked Questions About CK-12's AI Tutor, Flexi
Is CK-12's AI Tutor, Flexi free?
Yes, CK-12's AI Tutor, Flexi is completely free for all users and educational purposes. The CK-12 Foundation operates as a non-profit organization dedicated to increasing access to high-quality educational materials. They provide this AI tutor, along with their comprehensive digital textbooks known as FlexBooks, at no cost to students, parents, and schools. There are no premium tiers, subscription fees, or hidden in-app purchases required to unlock the tutoring features.
Is CK-12's AI Tutor, Flexi good for elementary students?
It is only partially effective for early elementary students. While the developer lists the app as suitable for grades one through five, the interface requires strong typing and reading comprehension skills. Younger students may struggle with the cognitive load of reading text-heavy AI explanations while simultaneously trying to learn new math or science concepts. It is much better suited for middle school and high school students who can navigate text-based chat independently.
What does CK-12's AI Tutor, Flexi teach?
Flexi primarily teaches core STEM subjects, including middle and high school math, physics, biology, and chemistry. It also covers applied science and career and technical education topics. Rather than delivering initial instruction, Flexi acts as a supplementary tutor to assist students with specific problem-solving steps, vocabulary definitions, and conceptual understanding while they read through their core curriculum materials.
How does CK-12's AI Tutor, Flexi compare to Khanmigo?
Both applications use artificial intelligence to provide step-by-step tutoring rather than simply handing students the direct answers. Khanmigo integrates deeply with Khan Academy's video-based ecosystem and currently requires a paid subscription for access. In contrast, Flexi integrates with CK-12's text-based FlexBooks and is completely free. Both tools successfully employ pedagogical scaffolding, but your choice will depend on whether your child prefers reading digital textbooks or watching instructional videos.
Has The Learning Standard evaluated CK-12's AI Tutor, Flexi?
TLS has not yet completed a Learning Standard evaluation of how well CK-12's AI Tutor, Flexi teaches. Its privacy policy has been reviewed for Data Transparency and does not yet document the basic protections (Level 1).
Is CK-12's AI Tutor, Flexi COPPA compliant?
A COPPA reference was not found in the reviewed privacy policy. This does not determine whether the app complies with COPPA. Policy review note: The policy does not mention COPPA.
Is CK-12's AI Tutor, Flexi FERPA compliant?
A FERPA reference was not found in the reviewed privacy policy. This does not determine whether the app complies with FERPA. Policy review note: The policy mentions "student records" but does not name FERPA.
Does CK-12's AI Tutor, Flexi have a children's privacy policy?
The reviewed policy includes a dedicated children's privacy section. Policy review note: The policy has a section headed Children's Privacy.
Does CK-12's AI Tutor, Flexi sell student data?
A statement ruling out data selling was not found in the reviewed policy. This does not establish that the app sells student data. Policy review note: The policy does not say that CK-12 does not sell personal information.
Can you delete your data from CK-12's AI Tutor, Flexi?
The reviewed privacy policy describes account deletion. We have not tested the deletion process. Policy review note: Users can ask to have their account removed.
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