ESF to Good Hope School Question

Is it very difficult for the children to get use to the class from international to English base school like from ESF Clearwaterbay to Good Hope School. Cause I know many from St. Catherine go to Good Hope. Or is St Catherine different from ESF Clearwaterbay. ANd is it difficukt to get it to ESF Clearwaterbay. I m living in Clearwater bay. When is the best time for applying. My child was born Aug 2003. Thanks