I claimed 2 children as dependents in 2018. When doing my taxes no longer qualify (no more school). I now have to repay my Obamacare subsidy. Do I have any options

You can choose to prorate the amounts with the taxpayers who are no longer on your return. You don't have to take the entire 100% yourself. You can each take 33% or however else you choose to split it up. It is between you. See the screenshots below.

If you do elect to take the entire 100%, you can get on an Installment Agreement with the IRS.

The best thing you can do is pay it before April 15 this year. If you can't you can fill out Form 9465 Installment Agreement Request. You will be liable for penalties and interest.

Understand your agreement & avoid default

• Your future refunds will be applied to your tax debt until it is paid in full;
• Pay at least your minimum monthly payment when it's due;
• Include your name, address, SSN, daytime phone number, tax year and return type on your payment;
• File all required tax returns on time & pay all taxes in-full and on time (contact us to change your existing agreement if you cannot);
• Make all scheduled payments even if we apply your refund to your account balance; and
• Ensure your statement is sent to the correct address, contact us if you move or complete and mail Form 8822, Change of Address (PDF).

For complete information, see https://www.irs.gov/individuals/payment-plans-installment-agreements.