In the first and second grade texts, the lesson began with an example followed by a
definition or a definition followed by an example. All these examples used models, such as
area models and discrete models. The lesson was followed by a set of exercises for practice.
Almost all the exercises used models similar to what was presented in the lesson.
In the third, fourth, and the fifth grades, the lesson included a quick set of questions to
review what had been presented in previous lessons or grades. Vocabulary words were
highlighted in a box. Although there was some difference in the format of the lessons, all
included questions or word problems that had been solved. The solutions for some of these
problems were presented as activities that often suggested the use of manipulatives. These
activities occupied 14% of the problems in the third grade and 19% in the fourth grade, but
only 7.7% in the fifth grade. The lesson usually began with a word problem or a question
followed by a definition of terms used or an illustration of how to solve the problem. Then
a solution was provided (Fig. 4). After the first question or word problem and solution, the
mathematical procedure was introduced. This sequence was repeated, depending on the
concepts presented in the lesson. The lesson was followed by a large set of practice
exercises.