An in-depth evaluation of standard English instruction in fourteen primary grade classrooms in the Michigan migrant education summer program was undertaken in 1971 in an effort to describe the actual normal teaching patterns existing in the classrooms. The children in those classrooms averaged 8 years of age, and 90% of all pupils had Spanish surnames. There was a significant gain in their ability to speak standard English over the summer. Teachers tended to shape the interactions of pupils and aides over time to a more consistent pattern of behavior and to encourage group responses over single pupil responses. Those teachers using choral response and a balanced amount of both positive and negative reinforcement obtained the highest gains. The areas of linguistic interference with which pupils seemed to have the most difficulty were medial sound pronunciation, past tense, past participle, and the comparative. There was an improvement with age in subject-verb agreement, plurals, and the past participle. Recommendations suggest that teacher training aim at instructing teachers in maintaining consistency in instruction, encouraging group responses, and balancing positive and negative reinforcement. Related documents are RC 006 240 and RC 006 241. (Author/MJB)