This instructor's guide consists of materials for use in helping students enrolled in postsecondary vocational or technical education programs to master pretechnical mathematics skills. Addressed in the 17 units of the guide are arranged under the following headings: Whole Numbers (whole number notation; addition, subtraction, multiplication, and division of whole numbers; mixed computation of whole numbers; and estimation of whole numbers); Fractions (fraction notation, addition and subtraction of fractions, and mixed addition and subtraction of fractions); and Decimals (decimal notation; addition, subtraction, multiplication, and division of decimals; and mixed computation of decimals). Each unit contains some or all of the following components: a unit objective, specific performance objectives, suggested activities for the instroctor, a list of references, information sheets, transparency masters, assignment sheets, a test evaluation, and test answers. (MN)