What Level of Tutor Interaction is Best?

Razzaq and Heffernan (2006) showed that scaffolding compared to hints on demand in an intelligent tutoring system could lead to higher averages on a middle school mathematics post-test. There were significant differences in performance by condition on individual items. For an item that proved to be difficult for all of the students on the pretest, an ANOVA showed that scaffolding helped significantly (p < 0.01). We speculated that the scaffolding had a greater positive effect on learning for this item because it was much more difficult for the students than the other items. We thought that this result warranted a closer look at the link between the difficulty of an item and the effectiveness of scaffolding. In this paper, we report on an experiment that examines the effect of math proficiency and the level of interaction on learning. We found an interesting interaction between the level of interaction and math proficiency where less-proficient students benefited from more tutor interaction and more-proficient students benefited from less interaction.