This volume presents a partial description of the lessons in the preliminary version of the PLATO fractions curriculum. Each lesson has three parts: review, new material, and a student-selected option. Students receive immediate feedback from the computer as they progress through each lesson. Five groups of lessons are described: meaning of fractions, mixed numbers, equivalent fractions, addition and subtraction (like denominators), and addition and subtraction (unlike denominators). An outline and flowchart is presented for each group. For each lesson within a group, a statement of purpose, a brief description, and sample computer displays are provided. (SD)