You may carry over only that portion of the credit that you do not apply to tax. You cannot carry over any amount that you paid that was more than the amount allowed as a credit. For example: in the current tax year, John, a single person, paid $400 to School A for extra curricular activity fees for John's child. Tor the current tax year, John is allowed a credit of $200. His tax due was $100. John may carryover $100 of the unused $200 credit to the next tax year. John cannot claim any credit for the $200 fee he paid that was more than the allowable credit ($400 minus allowable credit of $200).