Modeling allows students to become more effective designers. High school technology and engineering students engage in engineering design challenges as part of traditional instructional practices. Model-eliciting activities (MEA) present students with opportunities to elicit mathematical thinking that facilitates modeling. Students (n = 266) from four high schools completed a MEA and design challenge procedure. The research design utilized a quasi-experimental method, post-test only, with homogenous matching comparison groups based on possible confounding variables. A rubric was used to measure student design performance. Students in the comparison group (n = 124) completed a traditional design challenge and were assessed on their design performance. Students in the treatment group (n = 142) completed a MEA, a traditional design challenge and were assessed on their design performance. An analysis of covariance (ANCOVA) was used in order to discover if the difference in average design challenge rubric score from comparison group (42.56) to the treatment group (45.18) was statistically significant. A one-way multiple analysis of covariance (MANCOVA) was used to indicate if the differences in student average scores in each rubric category were significant. The ANCOVA did not reveal evidence supporting the research question with regard to overall design performance. The Pillai's Trace MANCOVA test results were significant. Four design rubric categories were found to be significantly different: Criteria, Proposal, Test/Evaluate, and Communicate. The findings in this study suggest that MEAs significantly support design-based classroom activities. While overall student design performance was reported to show no significant increase, aspects of design displayed significant improvement. Technology and engineering teachers should examine MEAs as potential curriculum enhancements in their design-based classrooms.