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There's probably a lesson here for ACT software and diagrams:
For Some Reason, These Quantum Mechanics Toys Didn’t Catch On
Designed in the 1960s, these clever blocks were intended to help students grasp arcane quantum abstractions
Reminds me of this game: https://csferrie.com/2018/12/13/brakets/
That game looks terrific! I think it'd be much easier to play with different notation. The , , , , and aren't intuitive unless you already know QM.
Maybe it was purposed to teach QM notation.. I think you can actually buy this card game somewhere, Chris actually had it produced somehow.