The sessions occurred three times a week, during the children’s regularly
scheduled mathematics period. Most sessions took place in a small, quiet room with two
desks and chairs. Occasionally, the sessions were held in an empty classroom. Sessions
took place from 1 p.m. to 1:40 p.m. on Tuesdays and Wednesdays, and from 10:40 a.m.
to 11:20 a.m. on Fridays.
Procedures
Protocol for the teaching phase of the experiment. The general format for the
experiment was as follows: 1) students were initially taught the dot positions on numbers
1 to 9,2) students were then taught to solve nine progressively more difficult types of
addition problems using the dot-notation method.