I decided to try out a wireless doorbell on my portable classroom last year, and I really like it. There’s something about the sound of the bell over pounding on the door that I love. It’s not too expensive to get a doorbell, and they are easy to set up. Mine was purchased at either Lowe’s or Home Depot.
The button outside of the classroom is powered by a CR2032 lithium battery and is attached onto the wall with a heavy duty sticker.
The part that actually emits the bell sound sits on my desk and is battery powered as well (3 C batteries).
Having a classroom doorbell has been great. I thought the bell sound might get annoying ring after ring, but I was wrong. I’m so glad I decided to try it out.