No, I do not allow a deck of cards to babysit my children,
BUT...
I do recommend it for keeping kids occupied for a few minutes while teaching them a thing or two.
Like reading books...
Card games go way back as a form of education and entertainment.
(And some peace and quiet for Mum)
Solitaire can teach:
Understanding
Strategy
Persistence
Entertainment
I would not recommend teaching Black Jack, 21 or any gambling (for instance: betting pennies like my father did with me) because it could certainly promote bad things, but I do feel that a few card games wouldn't hurt their brain or your schedule or stress level...
It your kids are between the ages of 8 and 11
teach them solitaire.
In my house it was like magic!