TurboTax is not setup to handle multiple school district returns. You can try these steps provide by RobertB4444 "TurboTax is not set up to help you prepare multiple SD100s so you will have to trick it into it.
Enter SD4201 into the federal return. Go through the entire return process as though you were only filing one school district return.
After you have completed everything then go back in the federal return and change the school district. This should have no effect on anything except the SD100 form.
Change your estimated payment and print out and mail the second school district return."
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