Should i tell her i like her or should i wait?!?!?!??!?

ok. this girl that ive liked for a really long time has jsut broken up with her boyfriend like 2 weeks ago...should i be straightforward and tell her that i like her or should i wait a lil while longer because she barely broke up with her boyfriend,...and me and this girl have had a past, but then she moved away for a while, but now shes back...so yeah should i wait a couple more weeks or just tell her...?? any advice would be help ful...thankss! =] oh and by the way we're in high school...