According to https://www.tax.virginia.gov/who-must-file, VA filling requirement is $11,950 for a single taxpayer. If your 15 year old is going to make less than that the entire year then she could claim an exemption because she will be under the filling limit for the year. If she might make more for the 2024 tax year, then it is best to claim 1 on the VA-4P.
