I personally think AP is much more flexible. IB is a package deal, you have to take whatever they are asking you to do: 6 subject at the same time. AP is subject based and you can choose which subjects and how many to do.
If you are target American U, of course doing AP is better as it is more recognized in the states. But if you have no idea of where to study in the future, then IB is a wise option.
As I know, ICS takes SAT, AP is optional.
Moroever, the school is American style, it is not that suitable if you would send your kids to England.
Did you have offers at both schools??
Many thanks BK mom's comments.
I already submit appliction in both school's secondary. I don't know what are they testing.
I m now gathering the background information and comparing between. Just in case, I have a chance to choose one of them. OR fail in both of them.
So, any more comments between both of these school? Thanks!
Advise you to apply to as many schools as possible. It's likely that neither ESF nor ICS will grant you even an interview unless there are students leaving after primary.