TOPEKA, Kan. (AP) — The Kansas Senate has unanimously approved a bill to rewrite the rules for teachers, school administrators and other public employees who return to work after retiring. The Senate's 40-0 vote Tuesday sends the measure to the House. The state allows public employees to retire but return to work and earn up to $20,000 a year while drawing their pension benefits. Schools regularly use the program to bring veteran workers into hard-to-fill positions. The working-after-retirement program is due to expire at the end of June. The bill extends the program for two years but then makes changes, starting in July 2017. The changes are designed to prevent workers and employers from setting up post-retirement jobs before a worker retires. Also, workers would be allowed to earn $25,000 in their post-retirement jobs.