As an employee that works directly with students, Child Abuse Mandated Reporter Training is required once a year. This training can be completed for free at
https://mandatedreporterca.com/.
You are mandated to report any instance of suspected child abuse or neglect. Reporters are not required to investigate. Report any reasonable suspicion of abuse to the appropriate law enforcement agency immediately. California County Child Abuse Reporting telephone numbers and 24-hour hotlines can be found at https://www.cdss.ca.gov/reporting/report-abuse/child-protective-services, to assist you with reporting. As a mandated reporter, your identity will be confidential. Note that you can discuss the issue with your immediate supervisor, but this does not take the place of reporting any reasonable cause for suspicion. If you suspect there is abuse or neglect, it must be reported.
Be aware of the warning signs of neglect, emotional, physical, or sexual abuse. A useful summary of warning signs can be found here at
https://www.cde.ca.gov/ls/ss/ap/childabusereportingguide.asp.