My son is working on a school project in which he's the business owner.  He likes this font for his receipts.  Anybody know the name of it?

This kind of fonts doesn’t usually exist as regular digital typefaces, but live inside of the machines used to print them.

However, if you look for something like “fake receipt [font]”, you will find many suitable alternatives.

I agree that it's quite unlikely that you find an exact match, but as @Riccardo Sartori said, there are a few that try to go the fake route, complete with uneven outlines. 

Merchant Copy would be one of those:

Or you could just go with any monospaced font that has a reasonably thin version, maybe even compressed/condensed. 

Like Input Mono:

(using the Compressed version here with alternative style set 13 to turn off the dots in the zeros)