Hello my son told me that in p.e he was doing jumping jacks and running and his "chest was in pain" please help?

CHEST PAIN: Does he have a heart problem before? If not, have him checked if persistent. Occasionally they have chest pain with too much exercise.

See his Dr: Could be asthma / allergies / acute illness / musculoskeletal pain / lack of conditioning / .....Or of course something more serious--although unlikely as is in at least grade school (made it this far...). Needs a good history and exam to sort out cause of symptoms.