To address the need for enhanced career and college readiness, a classroom guidance curriculum was studied using a pretest–posttest nonequivalent groups quasi‐experimental design. Data from 163 ninth‐grade students enrolled in a low‐performing high school were analyzed via hierarchical linear modeling. The analyses indicated a treatment effect on postsecondary education‐going knowledge and career and college readiness self‐efficacy, accounting for 100% of the variance explained by classroom‐level factors and indicating potential for the classroom guidance curriculum. The findings encourage career and professional school counselors to proactively employ similar classroom guidance programs aimed at encouraging high school students to consider postsecondary education opportunities. Future research could focus on component analyses of the curriculum, broadening the target populations, using mixed‐method designs, and additional validity studies of the dependent measures.