Individual differences in collaborative explanations during learning were analyzed to detennine effects on problem solving. Twenty-five university students with no prior programming experience worked through a sequence of programming lessons. For the Target lesson, subjects studied instructional texts and examples in either mixed performance-level dyads (collaborative dyad group) or individually (individual group) prior to individual programming activities. The collaborative dyad subjects were divided into equal sized groups of high-benefit and low-benefit dyad subjects based on Target lesson programming performance. Betweengroup analyses of the characteristics of the explanations generated by high-benefit and lowbenefit dyad subjects were investigated, including (a) explanation and metacognitive strategies, (b) content of elaborations, and (c) manner of generating elaborations. High-benefit dyad subjects were found to generate both a higher quantity and higher quality of elaborations. These results are compared to findings from prior research