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

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

location_on Pittsburgh, United States
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.
CTAG is laying the foundation for a revolution in high school biology education.

Many people have contributed to CTAG over the years. Albert Corbett, one of the founders of Carnegie Learning, was the PI for most of the project. Aaron Mitchell, the head of the biology department at CMU, has played an important role, as has D.J. Brasier. Benjamin MacLaren has been a principle designer, and the principle developer since the beginning, as well as the source of the idea for Pathway Algebra as the basis of CTAG.


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Innovation Overview

14 - 18
Age Group
Updated on May 7th, 2021
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  As AP classes expand schools are struggling to find teachers even for traditional and outdated text-based approaches.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:


Achievements & Awards

May 2019
March 2019
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Inspired to implement this? Here's how...

Sign up for CMU's OLI, and register for the CTAG-Guest cours
In five minutes, anyone with a web browser can be using CTAG.
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