Unfortunately schools are breeding grounds for sickness. Alot depends on the kid. Was he sick much before school, well if he wasn't that may be why he is getting so much now, he's not got the immunity built up yet. My twins were around kids and in preschool as well, however the first couple of years of school were pretty bad, for us at least. Last year in 2nd grade was alot better and now they're in 3rd so we'll see. My hope is with each year their immunity will get better and better.
My advice for meds.....mucinex--it's great for thinning out the mucous so they aren't as stuffy, snotty, or cough as much. Also delsym--great for cough, but make sure not to get the mucinex that has cough suppressant in it, it doesn't work that well anyway and you can't use that and the delsym. So, keep in mind it will get better and goodluck.