It starts with a wireless doorbell that can be purchased at the local hardware store or ordered on-line. I ordered mine from Amazon. There were a wide selection to choose from. Some plug into an outlet, others run on batteries. Most have a variety of tunes that they can play.
My doorbell runs on batteries and came with two remotes. Mine actually came with the batteries. I keep one remote on my technology cart and the second remote next to my small group table. I have also placed it in my pocket if I think I might need it and don't want to walk over to where it is normally located.
The doorbell part hangs on the wall using a push pin. It is about 4 inches tall. Very small and inconspicuous, but loud enough for kids to hear.
Once I push the button, the tune begins to play and all my kids stop what they are doing. They place their hands on top of their head and look at me.
The tune is long enough (but not too long) that by the time it ends everyone is looking at me silently.
Once you give it a try you will wonder how you ever managed without it.
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