It's not a live stream, but if you want a live video conference tool to use with students, surely the best option in town is nostr:nprofile1qy88wumn8ghj7mn0wvhxcmmv9uq32amnwvaz7tmjv4kxz7fwv3sk6atn9e5k7tcqyqfllpq59fjjvfz3ynqcp76ngt82zvx4trlv04ygqxw3mtn64jsc5s5jswk

I use that with my students for live classes, and it works great, but perhaps you need something else? It's totally free and works in your browser, no download required. I use it on my desktop, but I suppose it should work on Android phone too.