I agree with what you say and you make valid points, however you also have to look at the motive behind the unfinished assignment... If they failed to complete the assignment because they didnt understand the assignment and couldnt get help in time thenthey should be assigned cain time to help instead of ASI. however on the other hand, if they just dont care, then you might as well send them to ASI or detention.

The idea of asi really depends on how much they did, why they didn't do the assignment and what they where doing instead of the homework. it is a hassle for parents to come an get their child after school and it often conflicts with sports and other electives.