My son has to build a project for his science class that is “useful “. It can be anything as long as it is original. He wants to build a device that can be put on the mailbox so that when the mailman opens the box, a switch is triggered that sends a message to his phone telling him that he’s got mail. How hard is this to do? Can anyone give me some advice on what would be required and where to buy it? I was hoping to get an existing device like a “Ring” doorbell and rig it so it calls the phone when the mailbox opens. Basically,I’m a mom with very little electronics xp that wants to help her son pass his class. Any suggestions??