An ongoing four-year ethnographic study of two cohorts of English-as-a-Second-Language (ESL) learners enrolled in mainstream Canadian primary school classrooms is described. The two cohorts are: (1) a group of six children observed from the beginning of kindergarten through the end of grade 2, and (2) five children observed from early kindergarten through grade 1. The language backgrounds of the children include Chinese, Polish, and Punjabi. Classroom observation of the children focused on classroom practices that appear to facilitate or inhibit learners' acquisition of the language used within this community. Practices facilitating access were found to include daily use of choral speech (poems, chants, series of items), songs, and rhymes. Practices blocking access included teacher-led "discussion" using the inquiry-response-evaluation method and small-group discussions in which classroom hierarchy and talk conventions are strictly enforced and which appear to inhibit interaction. Excerpts of classroom conversation are offered as illustration. (MSE)