Globetechnology: "The artificial intelligence built into the Carnegie Learning program helps set it apart. Not only does the program present drills according to a student's weaknesses, it also watches the work step by step, detecting where the student stumbles, and chimes in when necessary.

'People solve problems in different ways,' said Ken Koedinger, a professor of human-computer interaction and psychology at Carnegie Mellon, and a co-founder of Carnegie Learning. 'So a student who solves a problem one way gets a different hint than a student who solves in a different way. You don't get that with computer-aided instruction systems.'"