105 ILCS 5/24-6
The school boards of all school districts, including special charter districts, but not including school districts in municipalities of 500,000 or more, shall grant their full-time teachers, and also shall grant such of their other employees as are eligible to participate in the Illinois Municipal Retirement Fund under the "600-Hour Standard" established, or under such other eligibility participation standard as may from time to time be established, by rules and regulations now or hereafter promulgated by the Board of that Fund under Section 7-198 of the Illinois Pension Code, as now or hereafter amended, sick leave provisions not less in amount than 10 days at full pay in each school year. If any such teacher or employee does not use the full amount of annual leave thus allowed, the unused amount shall be allowed to accumulate to a minimum available leave of 180 days at full pay, including the leave of the current year. Sick leave shall be interpreted to mean personal illness, mental or behavioral health complications, quarantine at home, or serious illness or death in the immediate family or household. The school board may require a certificate from a physician licensed in Illinois to practice medicine and surgery in all its branches, a mental health professional licensed in Illinois providing ongoing care or treatment to the teacher or employee, a chiropractic physician licensed under the Medical Practice Act of 1987, a licensed advanced practice registered nurse, a licensed physician assistant, or, if the treatment is by prayer or spiritual means, a spiritual adviser or practitioner of the teacher's or employee's faith as a basis for pay during leave after an absence of 3 days for personal illness or as the school board may deem necessary in other cases. If the school board does require a certificate as a basis for pay during leave of less than 3 days for personal illness, the school board shall pay, from school funds, the expenses incurred by the teachers or other employees in obtaining the certificate.
Sick leave shall also be interpreted to mean birth, adoption, placement for adoption, and the acceptance of a child in need of foster care. Teachers and other employees to which this Section applies are entitled to use up to 30 days of paid sick leave because of the birth of a child that is not dependent on the need to recover from childbirth. Paid sick leave because of the birth of a child may be used absent medical certification for up to 30 working school days, which days may be used at any time within the 12-month period following the birth of the child. The use of up to 30 working school days of paid sick leave because of the birth of a child may not be diminished as a result of any intervening period of nonworking days or school not being in session, such as for summer, winter, or spring break or holidays, that may occur during the use of the paid sick leave. For paid sick leave for adoption, placement for adoption, or the acceptance of a child in need of foster care, the school board may require that the teacher or other employee to which this Section applies provide evidence that the formal adoption process or the formal foster care process is underway, and such sick leave is limited to 30 days unless a longer leave has been negotiated with the exclusive bargaining representative. Paid sick leave for adoption, placement for adoption, or the acceptance of a child in need of foster care need not be used consecutively once the formal adoption process or the formal foster care process is underway, and such sick leave may be used for reasons related to the formal adoption process or the formal foster care process prior to taking custody of the child or accepting the child in need of foster care, in addition to using such sick leave upon taking custody of the child or accepting the child in need of foster care.
If, by reason of any change in the boundaries of school districts, or by reason of the creation of a new school district, the employment of a teacher is transferred to a new or different board, the accumulated sick leave of such teacher is not thereby lost, but is transferred to such new or different district.
Any sick leave used by a teacher or employee during the 2021-2022 school year shall be returned to a teacher or employee who receives all doses required to be fully vaccinated against COVID-19, as defined in Section 10-20.83 of this Code, if:
For purposes of return of sick leave used in the 2021-2022 school year pursuant this Section, an "employee" is a teacher or employee employed by the school district on or after April 5, 2022 (the effective date of Public Act 102-697) .
Leave shall be returned to a teacher or employee pursuant to this Section provided that the teacher or employee has received all required doses to meet the definition of "fully vaccinated against COVID-19" under Section 10-20.83 of this Code no later than 5 weeks after April 5, 2022 (the effective date of Public Act 102-697) .
No school may rescind any sick leave returned to a teacher or employee on the basis of a revision to the definition of "fully vaccinated against COVID-19" by the Centers for Disease Control and Prevention of the United States Department of Health and Human Services or the Department of Public Health, provided that the teacher or employee received all doses required to be fully vaccinated against COVID-19, as defined in Section 10-20.83 of this Code, at the time the sick leave was returned to the teacher or employee.
For purposes of this Section, "immediate family" shall include parents, spouse, brothers, sisters, children, grandparents, grandchildren, parents-in-law, brothers-in-law, sisters-in-law, and legal guardians.
105 ILCS 5/24-6