High Schools -- independent, charter, public and private -- are gathering solid evidence of their students’ critical thinking and mathematical reasoning ability using Insight Assessment instruments tailored for the high school student population. Clients use our valid and reliable entry data to inform admissions and individual student advising for college preparation.  Assessment data can be used to identify which students would most benefit from focused training in reasoning and decision making and to predict successful college admission or the licensure of trade candidates. Other uses include validating the effectiveness of subjective competency-based teaching approaches and guiding curriculum innovations to respond to group strengths and weaknesses in critical thinking.