The Illinois School Code requires that children entering kindergarten (or first grade if kindergarten was not attended) and sixth grade must have had a physical exam within one year prior to starting that grade level. Students of any age transferring from a school outside Illinois must also have had a physical within the last year.
The Illinois Department of Public Health requires specific immunizations for students enrolling in public schools. Students are required to show proof of immunizations at the start of the school year. (Kindergarten: DTaP, Polio, MMR, Varicella) (6th grade: Tdap, MCV, Hep B)
Illinois Immunization requirements:
https://dph.illinois.gov/topics-services/prevention-wellness/immunization/minimum-immunization-requirements.html