Filing taxes

It depends. It sounds as if she is under the income filing limit for the federal return but please see the exceptions below. 

For the state return, they all have different requirements but if you look up the state tax website for filing requirements, they should be be listed.  If she files a state return, she may qualify for all of her withholding to be returned as a refund.  

The state will not accept an e-file, if the federal was not accepted as an e-file. So if she files just the state, she will need to file by mail.  I would recommend to prepare both the federal and the state in TurboTax, she should qualify for the free version, and see if she qualifies for any refundable credits. If she does not, she can choose to file by mail and then only mail the state portion. 
 

You also must file a federal return if:

• You had $400 or more in self-employment net earnings (gross income minus expenses)
• You had marketplace health insurance and you received advance payments for the premium tax credit
• You (or your spouse if filing jointly) received health savings account, Archer MSA, or Medicare Advantage MSA distribution
• You had wages of $108.28 or more from a church or qualified church-controlled organization that is exempt from employer social security and Medicare taxes
• You owe any special taxes, including any of the following:
  •  Alternative minimum tax
  • Additional tax on a qualified plan, including an individual retirement arrangement (IRA), or other tax-favored account
  • Household employment taxes
  • Social security and Medicare tax on tips you didn't report to your employer or on wages you received from an employer who didn't withhold these taxes
  • Uncollected social security and Medicare or RRTA tax on tips you reported to your employer or on group-term life insurance and additional taxes on health savings accounts
  • Recapture taxes