This publication continues the descriptions of the cognitive, psychomotor, and socioemotional measures used in all years of the Head Start Planned Variation Evaluation study. Included is a detailed examination of each measure, a discussion of the theory behind it, and a review of the available data on the measure's reliability, validity and other technical qualities. The last half of the document contains appendices relating to the procedures used in examining the quality of the data: (a) Test-Retest/Inter-Tester Reliability Study; (b) Eight-Block Sort Reliability Study; (c) Classroom Behavior Inventory Test-Retest Reliability Study; (d) Coding Reliability Study; (e) Classroom Information Form Reliability Study; (f) Parent Information Form Test-Retest Reliability Study; and (g) Quality of the Testing Procedure. Data tables are included. (SET)