Is there a way to get push notifications from a normal webserver?

I attend a public high school, and I don't like logging on to check my grades all the time. Is there a way to "ask" the server to send me a push notification when my grades change? I wrote a simple script in Python that essentially crawls the webpage every 5 minutes, logging on and determining if new assignments / grades have been added. If my grades have changed, the script sends me a text message. Although this method works, I can imagine it's not the most efficient way to get notified when my grades change because:

1. My grades don't change every five minutes.


2. I don't want to send suspicious web activity to my school district servers, logging on every 5 minutes of the day.

What's the best way to get push-like notifications from a server that doesn't utilize push technologies?