You can still deduct direct expenses you paid for supplies for your classroom, up to $250 per taxpayer. See https://www.irs.gov/newsroom/educators-can-claim-deduction-to-get-money-back-for-classroom-expenses
However, as Critter says, any contributions to a 501(c)(3) are deductible on the federal level, only if you itemize.
Note that on the state level, you MAY be able to deduct such contributions, because the Standard Deduction is still less than the federal Standard Deduction in some states.
What state do you live in?
