Using a mixed model, we evaluated effects of national 4-H hippology and livestock skillathon contests on youths' content knowledge, 21st century skills, and postsecondary plans. Hippology participants gained significant knowledge in all topics except breeds, and livestock skillathon contestants gained significant knowledge in all topics. The contests were similar in their effects on development of 21st century skills and postsecondary plans. Gains in content knowledge indicate that contest preparation is an effective method for increasing youths' technical knowledge. Additionally, findings suggest that contest preparation is a viable venue for 21st century skill development and that such skill development is not specific to topic.