A 3-year, three-part study investigated the learning strategies (LS) of children in grades 1-4 learning a foreign language (French, Spanish, Japanese) in an immersion setting and assisted immersion teachers in using LS for instruction. A sample of 72 high-rated and low-rated students were followed for 2 to 3 years. Professional development activities familiarized teachers with ways of incorporating LS into curricula. Data were gathered from students using think-aloud interviews and questionnaires concerning LS use and self-efficacy, and from teachers using interviews. Research focused on: (1) which LS are used by more effective and less effective learners; (2) whether and how the strategies change over time; (3) whether students using LS more frequently perceive themselves as effective language learners; (4) differential LS use by language; (5) relationship between language proficiency and LS use; (6) types of teacher development supportive of LS instruction in language immersion; and (7) immersion teachers' beliefs about effectiveness of LS instruction. Results are reported and discussed. Appended materials include information on LS, questionnaires, and interview forms. Contains 37 references. (MSE)