If you received a Form 1098-T, enter the information from the Form 1098-T exactly as it appears. Be certain that you do not check the box indicating that your daughter is enrolled at least half-time. (While she may be a full-time high school student, this question is only about post-secondary education.)

This should result in disqualifying your daughter for the American Opportunity Tax Credit, which is good, because you want to save the four years of AOTC for her actual undergraduate education. She should qualify for the Lifetime Learning Credit. The credit will be relatively small, as it will be based only on the tuition and fees for a few courses, but every bit helps.

For more information about educational benefits that will be available to help during your daughter's college years, please see IRS Education Benefits Comparison Chart.