Can I claim the American Opportunity Tax credit if I have been in college for over 4 years but don't have a BA? I got an AA and have been in my BA program for 3.5 years.

It depends.

You can only claim the American Opportunity Credit for four years.  Once you claim it for four years, you cannot use it anymore.  

You should review your tax returns to see how many years you claimed it in the past.  It is a credit per student and is limited to 4 years in total, regardless of who claimed the credit.   

If it has already used in the past four years, you will only be able to use the Lifetime Learning Credit or Tuition & Fees deduction.

American Opportunity Credit is available for the first 4 years of college while working towards a degree.  The maximum credit is $2,500 per eligible student, must be enrolled at least half time for at least 1 semester, and up to $1,000 can be refunded to you. 

Lifetime Learning Credit is not limited by the number of years in school and can be used for undergrad, graduate, and professional degree courses, including ones to improve job skills. 

The maximum credit is $2,000 per tax return, can be used when only taking 1 class, you don't need to be working towards a degree, and none of the credit is refundable. 

Chart comparing credits 

Tuition & fees deduction