Children's pronunciations of vowel clusters in synthetic words were analyzed in relation to common English words containing the same vowel clusters. Subjects were 436 elementary students of both high and low reading levels from a suburban, an urban, and a rural community. Discussion of the problem and procedures of the study are found in Part 1, RE 003 626; results and conclusions are found in Part 2, RE 003 627. Part 3 contains the bibliography and nine appendixes: (A) International Phonetic Alphabet Symbols for Phonemes of American English; (B) Four Forms of Vowel Cluster Multiple-Choice Test Used with Pilot Studies A and B; (C) Four Forms of Vowel Cluster Multiple-Choice Test Used with the Study; (D) Waterloo Subject's Code Number, Sex, Grade Level, Reading Score, and IQ Score; (E) Study Subject's Code Number, Sex, Grade Level, School, Reading Score, and IQ Score; (F) Summary of Reading Achievement Tests; Intelligence Tests, and Dates of Administration to the Subjects of Pilot Studies A and B and the Study; (G) F Values of Main Effects and Interactions for Analysis One; (H) F Values of Main Effects and Interactions for Analysis Two; and (I) Assumptions Underlying the Use of Analysis of Variance. (VJ)