Two experiments to develop psychometric and administrative data on instruments designated for a testing program with disadvantaged elementary school children were undertaken. These instruments provide measures of growth and development in such diverse areas as verbal expressiveness (the ITPA and the Hertzig/Birch scoring of the PSI), problem solving (Raven's Progressive Matrices), self-esteem (Faces and Coopersmith), and achievement motivation (Gumpgookies and Locus of Control). Both experiments involved test-retest assessments of reliability, and factorially balanced assessments of tester effects. The results are discussed with regard to reliability, validity, and suitability of these instruments within and across grade levels K-3. (Author)