(b-5) Among the many possible disciplinary interventions and consequences available to school officials, school exclusions, such as out-of-school suspensions and expulsions, are the most serious. School officials shall limit the number and duration of expulsions and suspensions to the greatest extent practicable, and it is recommended that they use them only for legitimate educational purposes. To ensure that students are not excluded from school unnecessarily, it is recommended that school officials consider forms of non-exclusionary discipline prior to using out-of-school suspensions or expulsions.

(b-10) Unless otherwise required by federal law or this Code, school boards may not institute zero-tolerance policies by which school administrators are required to suspend or expel students for particular behaviors.

(b-15) Out-of-school suspensions of 3 days or less may be used only if the student's continuing presence in school would pose a threat to school safety or a disruption to other students' learning opportunities. For purposes of this subsection (b-15), "threat to school safety or a disruption to other students' learning opportunities" shall be determined on a case-by-case basis by the school board or its designee. School officials shall make all reasonable efforts to resolve such threats, address such disruptions, and minimize the length of suspensions to the greatest extent practicable.

(b-20) Unless otherwise required by this Code, out-of-school suspensions of longer than 3 days, expulsions, and disciplinary removals to alternative schools may be used only if other appropriate and available behavioral and disciplinary interventions have been exhausted and the student's continuing presence in school would either (i) pose a threat to the safety of other students, staff, or members of the school community or (ii) substantially disrupt, impede, or interfere with the operation of the school. For purposes of this subsection (b-20), "threat to the safety of other students, staff, or members of the school community" and "substantially disrupt, impede, or interfere with the operation of the school" shall be determined on a case-by-case basis by school officials. For purposes of this subsection (b-20), the determination of whether "appropriate and available behavioral and disciplinary interventions have been exhausted" shall be made by school officials. School officials shall make all reasonable efforts to resolve such threats, address such disruptions, and minimize the length of student exclusions to the greatest extent practicable. Within the suspension decision described in subsection (b) of this Section or the expulsion decision described in subsection (a) of this Section, it shall be documented whether other interventions were attempted or whether it was determined that there were no other appropriate and available interventions. [...]

(d) The board may expel a student for a definite period of time not to exceed 2 calendar years, as determined on a case-by-case basis. A student who is determined to have brought one of the following objects to school, any school-sponsored activity or event, or any activity or event that bears a reasonable relationship to school shall be expelled for a period of not less than one year:

(a) No punitive action, including out-of-school suspensions, expulsions, or court action, shall be taken against truant minors for such truancy unless appropriate and available supportive services and other school resources have been provided to the student. Notwithstanding the provisions of Section 10-22.6 of this Code [105 ILCS 5/26-10-22.6], a truant minor may not be expelled for nonattendance unless he or she has accrued 15 consecutive days of absences without valid cause and the student cannot be located by the school district or the school district has located the student but cannot, after exhausting all available supportive services, compel the student to return to school.