Is it legal for my school district to force me to use my PTO for the high holy days?

I work full time as a paraprofessional in a public school district. I am paid hourly wage, 40 hours a week. I get a certain amount of sick and personal hours per year. I started working in December of 2020, so I haven’t had to deal with this yet. But, I am planning to work next year as well so I asked the district how I would fill out my time sheet if there was a Jewish holiday. They told me that because Jewish holidays were not recognized vacation days on the school calendar, they did not count and I needed to use my personal time. Is this normal or discrimination? Because it kinda feels like I end up with less personal days per year than everyone else just because I’m Jewish…