The rules shall prohibit the use of tobacco and the use or possession of alcoholic liquor, wine, or beer or any controlled substance as defined in section 124.101, subsection 5, by any student of the schools and the board may suspend or expel a student for a violation of a rule under this section.

The board of directors of a public school and the authorities in control of a nonpublic school shall prescribe procedures for continued school involvement with a student who is suspended or expelled for possession of a dangerous weapon, as defined in section 702.7, on school premises in violation of state law and for the reintegration of the student into the school following the suspension or expulsion.

The board of directors of a school district and the authorities in charge of a nonpublic school which receives services supported by federal funds shall expel from school for a period of not less than one year a student who is determined to have brought a weapon to a school or knowingly possessed a weapon at a school under the jurisdiction of the board or the authorities. However, the superintendent or chief administering officer of a school or school district may modify expulsion requirements on a case-by-case basis. This section shall not be construed to prevent the board of directors of a school district or the authorities in charge of a nonpublic school that have expelled a student from the student's regular school setting from providing educational services to the student in an alternative setting. If both this section and section 282.4 apply, this section takes precedence over section 282.4. For purposes of this section, "weapon" means a firearm as defined in 18 U.S.C. § 921. This section shall be construed in a manner consistent with the federal Individuals with Disabilities Education Act, 20 U.S.C. § 1400 et seq.

1. The board may, by a majority vote, expel any student from school for a violation of the regulations or rules established by the board, or when the presence of the student is detrimental to the best interests of the school. The board may confer upon any teacher, principal, or superintendent the power temporarily to suspend a student, notice of the suspension being at once given in writing to the president of the board.

2. A student who commits an assault, as defined under section 708.1, against a school employee in a school building, on school grounds, or at a school-sponsored function shall be suspended for a time to be determined by the principal. Notice of the suspension shall be immediately sent to the president of the board. By special meeting or at the next regularly scheduled board meeting, the board shall review the suspension and decide whether to hold a disciplinary hearing to determine whether or not to order further sanctions against the student, which may include expelling the student. In making its decision, the board shall consider the best interests of the school district, which shall include what is best to protect and ensure the safety of the school employees and students from the student committing the assault.

3. A student shall not be suspended or expelled pursuant to this section if the suspension or expulsion would violate the federal Individuals with Disabilities Education Act.

4. Notwithstanding section 282.6, if a student has been expelled or suspended from school and has not met the conditions of the expulsion or suspension, the student shall not be permitted to enroll in a school district until the board of directors of the school district approves, by a majority vote, the enrollment of the student.