Following a measles outbreak in 2015, California passed one of the strictest mandatory vaccination laws in the country.
It requires that all children attending school in the state have up-to-date vaccinations for 10 diseases: tetanus, diphtheria, measles, pertussis, mumps, rubella, hepatitis B, influenza B, polio, and chickenpox.
Under the California law, unvaccinated children are barred from attending public or private schools, as well as day care programs (there is the punishment that I agree with). The only permitted exemptions are for medical reasons.
https://www.healthline.com/health-news/should-parents-be-punished-for-not-vaccinating-children#3