Retirements and resignations should be given with sufficient notice to the school site or department to allow for an effective transition. If you plan on retiring, be sure to contact either CalSTRS or CalPERS a few months ahead of your planned retirement date.  Retiree health benefits vary by bargaining unit and you must retire with PERS or STRS within 120 days of separation to be eligible — refer to your contract or benefit office for more information. 

Link to Information about retirement

Link to Separation of Employment checklist