Yes, since she is under the income limits. Depending on her age, she can contribute $6,000 or $7,000 if she is over 50. Note: the money doesn’t have to come from her part time earnings; it could come from you. But she must earn as much as she contributes. And yes it would be a tax deduction. Or perhaps she would want to open a Roth IRA, which means though she gets not current tax deduction, the money grows tax-free for retirement. (With a traditional, deductible IRA, she will have to pay ordinary income tax on withdrawals.)
Go to Fidelity or Vanguard and they will help her open the account.
SPECIAL NOTE: She can still open an IRA for her 2019 income — up until the April 15th tax return due date! And if it is a traditional IRA that will give you a tax deduction on yur 2019 joint return.