In addition to avialable currency options, add a made-up symbol. Using this symbol would take away the feel of “money” in the game. Students would feel like they’re earning points or credits rather than money.
We could call them “Gimees,” a pun on “gimme” (give me’s), like “gimme those points!”
This is called GimCoin now, as per the recent EdTech release.
I would call the gimcoins