I really am getting myself worked up over this.

I dont want to ruin my daughters education so any advice anyone can give me here would be much appreciated.
She is due to take her GCSEs May 2009 and is a A* student who we are extremely proud of. I need to know if it would be better for her to take her GCSEs here first then we go over to Aus or go ahead this year as we were planning to do originally.
I'm not sure I really understand how the exam system works over there tbh. (thats why I wasnt a A* student

) Would her GSCEs mean much over there or not? She will be 16 in September so what school year would she be in if we leave this Summer?
I also have a boy who has just turned 13 in Jan (very proud of him too

)who is more into his sport rather than his education. I know he will be fine and throw himself into all the sporting activities available.
Please if anyone can help me with this or have been in the same situation I would love to hear from you.
Thanks.