Solving equations such as
3x 5 = 7
In the experiment to be modeled in detail 10 students ages 11 to 14 spent 6 days practicing solving such equations. The first day (Day 0) they were given private tutoring on this class of equations, using the unwind principle, and practiced paper and pencil solutions of such problems with a private human tutor. On the remaining 5 days they practiced on a computer the solution of three classes of equations:
0-step: e.g., 1x + 0 = 4
1-step: e.g., 3x + 0 = 12, 1x + 8 = 12
2-step: e.g., 7x + 1 = 29
The computer simulation reproduces this speedup.