When I was in seminary in Israel ya, there were the girls going out to eat, going shopping in malcha or Mamilla (malls)living it up like they were on vacation not living in Israel-a Makom Kadosh!, There are hypocritical people ya, they go to the frum camps, high schools but in seminary the girls listened to their non Jewish music, books, magazines,videos etc. and I went to a well known to be good frum seminary(I was shocked!)I wonder if the good frum boys yeshivas have the same issue?
My point really is you must know your child before sending him/her to Israel make sure you can trust 100% they know whats right and whats wrong!