The purpose of this study was to investigate the effect of instruction in alternative solutions on Taiwanese eighth-grade students' mathematical problem solving performance. This study was exploratory rather than experimental. Alternative-Solution Worksheet (ASW) was developed to encourage students' engagement with alternative solutions to mathematical problems during instruction. Data for this study consisted of students' problem solving scores on the pretest, posttest and ASWs. The results of this study indicated that students improved their problem solving performance after instruction in alternative solutions utilizing ASW techniques and students who performed better on ASWs tended to improve more on their problem solving performance. (Contains 1 footnote, 1 table, and 3 figures.)