This study investigated how engineering integrated science (EIS) curricula affect first-year technical high school students’ attitudes toward science and perceptions of engineering. The effect of the EIS participation period on students’ attitudes toward science was also investigated via experimental study design. Two engineering integrated science curricula (10 and 18 weeks) were purposefully designed and implemented for the study. Two important results emerged: (1) The EIS curriculum participation period (10 or 18 weeks) mattered in terms of changing students’ attitudes toward science and (2) A majority (>61%) of the students from both control and experimental groups who participated in the first EIS agreed that the curriculum positively affected their understanding of engineering practice. The results suggest that EIS is a potential pedagogical approach for reforming current science practice in technical high school programs to improve both students’ interest in science and career readiness. Implications for implementing EIS in technical high school settings are addressed.