40 ILCS 5/17-138
At the first meeting of the Board of Education in November of each year, the Board of Education shall appoint one of its members to serve, while a member of the Board of Education, on the Board of Trustees for a term of 2 years.
During the first week of November or as soon as possible thereafter, but not later than the third week of November, there shall be elected 2 members of the Board from the teachers other than administrators, who shall hold office for terms of 3 years, provided the trustee retains his or her status as a teacher other than an administrator, and other members to fill any unexpired terms. The election shall be by secret ballot conducted in person or by secure electronic ballot, and shall be held in such manner as the Board by bylaws or rules shall provide. Only teachers who are not administrators shall be eligible to vote in the election.
During the first week of November of 1995 and every third year thereafter, one contributor who is an administrator shall be elected a member of the Board. Beginning in November of 2022, the election under this paragraph shall take place during the first week of November or as soon as possible thereafter, but not later than the third week of November. This trustee shall hold office for a term of 3 years, provided the trustee retains his or her status as an administrator. The election shall be by mail ballot or by secure electronic ballot, and only contributors who are administrators shall be eligible to vote. The election shall be held in the manner provided by the Board by rule or bylaw.
During the first week of November or as soon as possible thereafter, but not later than the third week of November, of each odd-numbered year there shall be elected 3 members of the Board from the pensioners, who shall hold office for a term of 2 years while retaining their status as pensioners. The election shall be by mail ballot or secure electronic ballot to all service and disability pensioners, and shall be held in such manner as the Board by bylaws or rules shall provide.
All trustees, while members of the Board of Education or while administrators, teachers other than administrators, or pensioners, as the case may be, shall hold their offices until their successors shall have been appointed or elected and qualified by subscribing to the constitutional oath of office at the immediately succeeding regular meeting of the Board.
40 ILCS 5/17-138