Other reasons children go into foster care include having been abused or neglected and being in a home where violence takes place. Keeping children in their home is the public policy priority if it's possible to do so while maintaining the child's safety and well being, but when it is not possible, children are placed into governmental care.
Here is a snipet from the website of the Child Welfare LEague of America about child protection. (7/23/09)
Child protection is keeping children safe from child abuse and neglect. This is the foundation on which child protective services (CPS) is established and should always be the first goal of any CPS response. The CPS response begins with the assessment of reports of child abuse and neglect. If CPS determines the child is at risk of abuse and neglect or has been abused or neglected, CPS should ensure the child and his or her family receive services and supports from the public child protection agency and the community.
http://www.cwla.org/programs/childprotection/childprotectionfaq.htm#whatis
because some children are being sexchly abused and can not do will at school