I would play the games and things with her at home. To show her what they are like. Then I'd explain to her how doing things in a backdoor sort of way helps kids learn things that might be hard for them.
For instance, many parents enroll their kids in beginning dance. Then if they observe the class they see the kids maybe doing the hokey pokey or having grass skirts on and doing a goofy hula.
They say they aren't paying for their kids to "play".
I explain to them that a 3 year old isn't programmed to stand still and tap their toe on command. They are learning they have a right hand, there it is, and hey, I'm supposed to do something with it so I need to listen, okay, now I need to do something else so I need to listen to my teacher. In the Hula they learn step together step and hey, I have a hand and COOOOOL! I can make it move like an ocean wave, gonna do that again!!!! COOOOOL!
SO even though the parents see a silly game or non-dancing teaching the kids ARE learning things by doing these activities. The biggest thing is to listen and do what they are asked. Not like little automatons but like kids learning to process simple commands and performing the needed action.
Helping your child learn that skills can be learned isn't a breach of confidentiality, it's telling her that she can play these games at home with you and her friends only get a few minutes every now and then. She's having fun with you at home.
I think if she's smart she'll figure out that the students you are working with are working on specific skill building activities. Perhaps that is something that you can do with her too, talk to her about an area she is having a harder time then do some work that helps her improve. Then she can see how handy it is to have that new skill.
I would not ever tell her the WHY of what those particular classmates are learning and I know you'll be careful too.
Good job mom, getting an education is awesome!!