This study examined the effects of a teacher-led learning-strategy intervention program on fourth-grade students' reported use and perceived effectiveness of rehearsal and comprehension-oriented learning strategies. During 18 program units, teachers taught about learning and various learning strategies, including visualisation, elaboration and categorisation. Strategies were practised in math, language and science classes. Participants were comprised of 82 fourth-grade students in the intervention group and 387 fourth-grade students in the control group. Students' reported use and perceived effectiveness of learning strategies were assessed before and at least 4 months after intervention using a web-based word-memorisation task and associated reflection questions. The intervention group tended to use more comprehension-oriented learning strategies in post-tests, and the intervention group also showed an increase in perceived effectiveness of comprehension-oriented learning strategies. Still, rehearsal was evaluated as the most effective strategy in both the control group and the intervention group. Explanations for these findings and possible future directions are discussed.