Hey Hudson, I have performed things involving cards for a wide demographic of folks, and
who does or doesn't "get" a deck of cards can come from any age. But there are things you
can do to mitigate the risk.

Mindpro set out some of the issues, but there are some others. Luckily, all of these have
simple solutions you come across as you perform more.

Clubs is the most likely thing for a person not to know, most will be aware of spades
but might confuse them with the clubs.

If you think the demographic might not know a lot about cards, have someone sign the
card. This way they can follow the autograph as opposed to the "jack of clubs".

Make sure if a person chose a card, they show it to the people around them
in case they forget. (or lie)

I disagree that folks don't know what a queen or king is, some people trip over Jacks though.

One danger is asking folks to sign the face of the card, and they sign the back instead.
I always say: "can you sign the card (gesturing at the face of another card of the deck I'm holding)
anywhere you see white". This has solved that issue completely.

Avoid "cut the cards" unless you already determined that the person is knowledgeable.
I usually say: "can you lift up about half? great, put it there (gesture to the side)
and put that half on top" you just walked them through cutting the cards.
Don't do that if the person is handling the cards well, or indicated they play cards.

One thing you might consider, when approaching a group, ask if anyone wants to shuffle.
Someone who has never held a deck of cards is unlikely to volunteer, you also just
determined who in the crowd isn't shy.

Don't let the folks you are performing for not understanding cards put you off,
presented well, they will still enjoy it as much as anyone else.

I would avoid gambling themed routines or things involving a lot of dealing though.

That's a whole lot of dancing to do just to use cards! Many things that can go wrong or bad. Also, if he is shooting for creating a stage performance I certainly wouldn't recommend worrying about cards. His time, efforts, and skills can be much better served and directed than with using cards. Rarely will anything with cards get an auditorium of school age students to be amazed and create a legend.

All of this is thinking like a magician...a closeup magician.

You are correct, I wrote that assuming a walk around or close-up situation.

I really have never liked stuff involving cards in stand-up or stage, it
just isn't visible enough. On the last page we talked about
cards across, this works because the cards don't really matter.
This is also true for manipulation.

Hudson, whatever you decide to perform, be it cards, mentalism, or anything
else, make sure the audience can see and understand what's happening all
the way to the furthest person.