A school custodian at Kanoelani Elementary School in Waipio has been charged with sexually assaulting a student on campus.  Fifty-three-year-old James Holt was charged with third-degree sexual assault involving a minor under the age of 14. Holt has a court appearance Thursday. Police records show he was arrested last Wednesday at the school. Holt had worked for the Department of Education for 14 years.  Tuesday, students at the school were sent home with a letter informing parents and guardians about the arrest. The letter also explained procedures for safety are practiced regularly and the staff will continue to be extremely vigilant in keeping a safe environment.