This article investigates instructional strategies that scaffold students’ reading comprehension of science texts in Content-Based language Instruction (CBI) settings; especially, the reading strategies that enhance comprehension of content, language and cognitive Science Process Skills (SPSs). The subjects are upper-elementary science classes in five private and public schools that follow English CBI in Northern Lebanon. We implemented observation and causal-comparative studies that use both students’ means of scores on reading assessment tests, and statistical tests of significance, to measure the effectiveness of the applied reading strategies. Results indicate that the student sample groups that used general classroom reading strategies, such as question/answer relationships and context-clue analysis, during and/or after teachers’ explanation of the lesson, have insignificant differences among means of their test scores. The student sample groups that used these strategies before the lesson’s explanation scored significantly lower averages than those that used them during and/or after. Other reading strategies, such as home reading, produced insignificant differences. The cognitive model of L2/FL acquisition and the cognitive academic language learning approach (CALLA) are used to substantiate these results.

CBI, reading strategies, SPSs, science subject, cognitive model of L2/FL acquisition, CALLA, upper elementary, reading comprehension