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The Cognitive Tutor for Analysis in Genetics (CTAG) is not just for genetics!

CTAG embodies a mental model for biology that we call Pathway Algebra, which helps kids simulate & explain theories in science.

Even with reforms, biology still overwhelms students with minutiae. Too often students end up being taught to fill in multiple choice tests, rather than appreciate the beauty of biology, which is changing our lives in ways few people fully understand. A modern biology curriculum should help students solve problems in areas like cancer and Personalized Medicine, which are changing our lives.



HundrED shortlisted this innovation

HundrED has shortlisted this innovation to one of its innovation collections. The information on this page has been checked by HundrED.






March 2019
CTAG is laying the foundation for a revolution in high school biology education.

About the innovation

CTAG - A Web-based Cognitive Tutor for Problem Sovling in 21st Century Biology for Underserved Schools

There is a logic for "assembly line" and "signaling" pathways that geneticists routinely use, which has not been introduced into educational settings, apparently because nobody thinks students could learn this advanced logic.  Using the widely successful cognitive tutor technology developed at Carnegie Mellon, we developed a curriculum for "Pathway Algebra" that has about a dozen and a half lessons in it.  It was originally developed for CMU biology majors, but we are finding that, when delivered in a cognitive tutor, AP biology high school students, and freshman (including art and drama majors) learn this logic quite well.

While innovative curriculums are being developed, they all require extremely well-trained teachers on a very large scale.  This is completely unrealistic.  As AP classes expand schools are struggling to find teachers even for traditional and outdated text-based approaches.  The demand is growing and the supply is struggling to keep up.

AFTER you've watched the introductory video above, you can see a more detailed description of the core lessons in CTAG  at:


Implementation steps

Sign up for CMU's OLI, and register for the CTAG-Guest cours

Account Signup for CTAG (Cognitive Tutor for Analysis in Genetics)

(for guests, or the generally curious)

Getting a real taste of what CTAG is all about only requires signing up for an OLI account, which is free and easy.  If you have five minutes:

1. Go to:  http://oli.cmu.edu/

2. Click “Students” at the top right.

2. Click the sign labeled “Course Key Students” pointing left, and then “Register with a Course Key” at the LEFT on the next screen.

2. Click “Sign In” at the top right, and then “Sign Up” at the top right of the next screen.

3. Enter your first name

4. Enter you last name

5. Enter your email address.

6. Enter your email address again as your “Account ID”

7. Choose a password and enter it twice.   (Commit this to memory!)

8. Select “SIGN UP”

9. Click “CONFIRM ACCOUNT” on the next page.

10. Agree and submit on the next page.

11. Register for the course “CTAG-S19-Gst”  (WARNING:  This is NOT what students should use!)

Click “Enter Course” (but only after committing your password to memory! ;-) )

Clicking on a unit will take you to the instructional text for the unit.  

I recommend starting at the beginning to read about the philosophy of the tutor (i.e., Pathway Algebra),

   and to see an example of someone using the tutor.


   you can check out this YouTube video (which D.J. Brasier at Carnegie Mellon made up for his students):


(NOTE1:  There is a pointer to this video on the first page of CTAG after you log in and enter the course)

(NOTE2:  After you’ve created an account, you may go to http://oli.cmu.edu/ & click “Sign in” at the top right.)

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