Carnegie Learning has 3 main Algebra products, called Bridge to Algebra, Algebra I, and Algebra II, plus a set of three programs called Integrated Math I, II, & III that combines all algebra, statistics, probability, and geometry at the high-school level.
Carnegie Learning claims that all its products are research-based and they report some of the most impressive results on the market. All the products are based on their Cognitive Tutor platform which includes several notable features. According to their website, these are: Just-In-Time Help, Skills Tracking, and Constant Monitoring.
There was no free demo available from the website for any of these products, so my appraisal of how the software works is limited to verbal descriptions from the website and screenshots. From these limited materials, it appears that the primary method of instruction is presenting multiple choice problems to the student and assessing their skills/knowledge based on their pattern of responses. In this way, the programs feel like a series of assessments.
Just-In-Time Help consists of hints provided for each question. Every activity the student works on is correlated to a set of skills.
Skills Tracking consists of monitoring student performance on all of the underlying skills based on their work in the activities. Progress in each skill is presented to the student in a "Skillometer".
Constant Monitoring refers to the notion that the computer is keeping track of the student's mouse clicks, and keyboard entries, and updating its own "Cognitive Model" of the student. If the student's interactions are wrong, Constant Monitoring will "guide the student to a solution path." 
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