I know the whole deal is "solving math problems" so I just liken it to solving crossword puzzles or sudoku when explaning it to my mom
The "solving hard math problems" explanation is a stupid analogy. A better analogy is picking lottery numbers, but even that is not really the point. The point of mining is validating transactions.
Yeah. As a math student, I find that annoying. It's just poo-loads of the most trivial kind of computations.
The part I am still trying to figure out is how do transactions get processed after all bitcoins are mined? Since transactions are only attached to a valid bitcoin block and there are a finite number of bitcoins that will ever be produced, will we lose the ability to perform transactions once all bitcoins have been mined?
Miners will keep mining blocks, there as just no longer any block rewards. The miners now get their income from the transaction fees, so there is still incentive for mining. You can do mining, just keep hashing blocks, there does not need to be a BTC reward for every new block.