aries: I guess we’ll have to agree to disagree, because I see nothing wrong with a Yeshiva choosing to cater to a specific niche and feel that they are fully entitled to make all reasonable inquiries to insure incoming students match their criteria. There certainly is an important need filled by broad community schools, but specialized Yeshivos are also very important. Of course this enters a whole separate issue.
Everything you write about new students having a “clean slate” etc. is true, once the child has been accepted. However there is no reason a school should feel pressured to accommodate inappropriate students even if they may improve, they are fully entitled to select talmidim who have already demonstrated their abilities. We aren’t discussing 1st grade, 8th graders have had years to prove themselves already.