If a student is really "bad" they get punished by being kicked out of the school system permanently. In the US, when a student is expelled from a public school there are legal defenses s/he may call on to appeal the decision because public education is a legal civil right.

Before a student is expelled they may have been suspended many times or had multiple incidents of rule breaking documented. A student may also be expelled for a "first offence" if it is considered serous enough.

Ex*pul"sion (?), n. [L. expulsio, fr. expellere: cf. F. expulsion. See Expel.]

1.

The act of expelling; a driving or forcing out; summary removal from membership, association, etc.

The expulsion of the Tarquins. Shak.

2.

The state of being expelled or driven out.

© Webster 1913.