Yes, but you and the child’s other parent can’t claim the
same expenses.
According to an FAQ on the
Illinois Revenue website, you can claim the credit for a child you don’t claim
as a dependent on your tax return
“… if you are the
parent or legal guardian of an eligible student and you paid qualifying
educational expenses in excess of $250 to a public or nonpublic school in
Illinois. However, if your child's other parent or legal guardian files a
separate return and claims the K-12 education expense credit, you may not both
claim a credit for the same expenses and the total amount of credit claimed
between both parents or guardians may not exceed $750.”