
Computer Curriculum Corporation In 1967 the Computer Curriculum Corporation (CCC) was formed to market the materials developed through the IBM partnership. Niemiec and Walberg (1989) suggested that "no other CAI system has had such impact at the elementary level" (p.272). CCC materials are organized into twentyfour blocks at the different grade levels. Each of the blocks has five levels of difficulty. For example, in one mathematics sequence, the first level of difficulty in block one is sums to the number six. Level five, the most difficult level, requires that the student rename equations and supply the missing addends. Initial exposure to a block begins with a pretest which establishes the level of difficulty for the following day. With a pretest score of 85 per cent or higher the student is branched to the highest level of difficulty with the block. The student is instructed for five consecutive days. Each day's score determines the following day's difficulty level. CCC materials are also branched. A score of 85 percent or higher moves the student to the next higher level of difficulty. Below 60 percent correct, the student moves down to a lower level of difficulty. Each block is followed with a posttest. After every four blocks, a review lesson and a review test are administered. ( p. 272) References: Niemiec, R.P. & Walberg, H.T. (1989). From teaching machines to microcomputers: Some milestones in the history of computerbased instruction. Journal of Research on Computing in Education, 21(3), 263276. 
