Yes, you can deduct expense if the class offers a college credit. High school students (dual enrollment student) are not eligible for the American Opportunity Credit. However, if the course provides a college credit course, the student may qualify for the Lifetime Learning Credit or Tuition and Fees deduction.
Am I limited to the number of times I may use each of the education deductions or credits?
Would I be better off waiting until his college expenses are higher when he is a full time student in college vs
deducting just a few classes taken in High School?
Yes, the American Opportunity Credit can only be claimed four times per student (combined with the Hope Credit if applicable), so it is to your advantage to wait until you can maximize the benefit because it provides greater credits. There is no limit for the Lifelong Learning Credit but as indicated, it is not quite as generous (lower amount and nonrefundable).