Modifies provisions relating to teacher retirement

HB 644 allows retired certificated teachers (with teaching credentials) and retired noncertificated staff (like support workers) to return to full-time work in school districts with staffing shortages, without losing their retirement benefits. Retired teachers can teach up to four years if a district has a certified teacher shortage (capped at 1% of staff or five teachers), while retired noncertificated staff can work up to four years for noncertified shortages (capped at 10% of such staff or five employees). School districts must prove they tried hiring non-retirees first, posted vacancies for a month, and declared an active shortage before hiring. The law takes effect July 1, 2026, with districts covering retirement contributions and paying retirees based on standard salary schedules.