To be more specific:
Your school has a/some servers and when ever you request a website it goes through a gateway (router) then goes to a server. Your server will log everything you do whether it be on a laptop, school pc. The admins will ususally go through the logs once every 6 months (if they do it manually)
Put it this way last year i had someone do remote desktop with me and I only got found out 4 weeks ago