Close excess tabs - Excess tabs will slow down your internet, especially if they are streaming something such as a YouTube video.
Do only one thing at a time - If you watch Netflix or YouTube or any streaming service while you work on school work it would greatly help your internet to turn those off.
Check who else is using your wifi - If there are other people streaming or using the wifi that can greatly lower its speed.
If possible switch to using a wired connection - Having a wired connection will make your internet much faster.
Restart your router/modem - If nothing else works this can sometimes be useful as a last resort.