how to stop sudden entire desktop sharing by host?

We are using Zoom as an online classroom. The instructor (host) doesn't like breakout rooms, and doesn't seem to know how to adjust his settings so that when he shares his screen it does not completely take over whatever we are doing on ours (participants). This is very disruptive as he bounces between shares rapidly, so if you minimize it just takes over again and again and makes it impossible to work on anything as he is doing this. Most of us are limited to a single screen and cannot easily add one. Is there any way to keep the Zoom window minimized, or at least not takeover the desktop unless the participant allows it, for screen sharing?