Teaching assistants' beliefs regarding example solutions in introductory   physics
  As part of a larger study to understand instructors' considerations regarding the learning and teaching of problem solving in an introductory physics course, we investigated beliefs of first-year graduate teaching assistants (TAs) regarding the use of example solutions in introductory physics. In particular, we examine how the goal of promoting expert-like problem solving is manifested in the considerations of graduate TAs choices of example solutions. Twenty-four first-year graduate TAs were asked to discuss their goals for presenting example solutions to students. They were also provided with different example solutions and asked to discuss their preferences for prominent solution features. TAs' awareness, preferences and actual practices related to solution features were examined in light of recommendations from the literature for the modeling of expert-like problem solving approaches. The study concludes that the goal of helping students develop an expert-like problem solving approach underlies many TAs' considerations for the use of example solutions. TAs, however, do not notice and do not use many features described in the research literature as supportive of this goal. A possible explanation for this gap between their belief and practices is that these features conflict with another powerful set of values concerned with keeping students engaged, setting adequate standards, as well as pragmatic considerations such as time requirements and the assignment of grades. 
Shih-Yin Lin, Charles Henderson, William Mamudi, Chandralekha Singh,   and Edit Yerushalmi
physics.ed-ph