A vital goal of instruction is to enable learners to transfer acquired knowledge to appropriate future situations. For elementary school children in middle-high-SES schools, “explicit” instruction on the Control of Variables Strategy (CVS) has proven to be very effective at promoting transfer, even after time delays, when administered by human instructors [1], [2] and when administered by our computer tutor (“TED” for Training in Experimental Design). However, when the same instruction was delivered to students in lowSES schools, near—but especially far—transfer rates were lower. We discuss our findings of the predictors of transfer in this population, and an initial investigation assessing the causal status of one candidate factor for far transfer, understanding the logic of CVS. Finally, we discuss the potential implications of these findings for ways to adapt instruction to individual students.