to remove someone's name or your own name from a list, for example a list of members of an organization or of a medical care plan

Some preschool providers are willing to work with parents of children who hit or bite, but others quickly "disenroll" (in other words expel) the child. 有些学前教育机构愿意与打人或咬人的孩子的家长合作，但其他机构则很快就会让孩子“退学”（换句话说就是开除）。

You may enroll/ disenroll /change at any time during the year. 您可以在一年中的任何时候报名/退学/转换。