Yet another product my family enjoys has its very own pyramid scheme, and this one doesn't require you to do anything other than click here to get free $20 in classes. You can then either just take the free $20 and be done with it, or you can refer more people and get free credits as well.
Outschool has live Zoom classes for ages 3-18 on pretty much every topic you could imagine, and appears to have literally thousands of live classes during any given time block. Some of the academic classes we've tried have been hit or miss, but if you're looking for a couple hours of free COVID babysitting, use my free credit and sign up for a one-time social or activity class. There are a million classes on Minecraft, Among Us, Roblox, etc., in addition to the more traditional art and dance sorts of things. I've been using it for COVID babysitting and referring people to get more classes. There's no upper limit as far as I'm aware.
Also, Outschool seems to be constantly hiring teachers, and it doesn't require any qualifications. You can use the same link to sign up to teach whatever interests you.