They manage just fine. A lot of boys don't bother with the fancy trips abroad, only going on the compulsory camping trips once a year.
In any school you always get the one or two who go (or try to go) on every trip offered, but the vast majority aren't like that.
People always equate KES to be full of "rich kids", but in all honesty, the "richest" people I know have put their children into Grammar school.
There is a similar thread to this already, hope it can reassure youviewtopic.php?f=11&t=26126&