Hey Emma, I had the same problem. Tell your Phy. Ed teacher your problem and He/She will let you ride bikes or run track or something like that while the others swim. It all works out good, and if the other kids ask you why you don't swim, tell them you're allergic to chlorine(can't spell).You could even tell that to your teacher and your mom could write a note to back it up. I hope this helps! Your Friend, Ashley