"Old enough" ???
It is still very much in the stores right now. There are two or three versions and you can get a single pie box or one that makes two pies.
If you make it right the crust is very good. I think it is flat and greasy plain but add your own toppings.
There was a pizza dough dry mix in the stores for quite a while that I can't find anymore. I think it was Chef Boyardee that packaged it - and it might be that same dough mix that's in those pizza kits.
I used to make the pizza kits when my oldest niece would come stay with me, when she was 2-3. That's the only thing we could count on her to eat, so we made a big production out of it. It was a fun time in the kitchen as she could "help" while I chopped all the veggies and toppings for it and she would put them on the pizza dough.
The dry mix I had been getting was so handy. I think the small canister would make 6 pizza crusts in all. You could just measure out however much you wanted to use. I don't have a stone, just used an aluminum pizza pan or even a baking sheet, for two smaller 7-8" rounds.
It took exactly 20 minutes to rise and was always perfect. I used cornmeal on the pan so the dough would stay in place when I formed it.
I'm always amazed at the folks who will plunk down $8-10 for the biggest frozen pizza from the grocery store. I've only tasted one once and never again. I will buy one of the cheaper ones and add my own Italian sausage, pepperoni, onions, sun-dried tomatoes, homemade pesto, green peppers, Feta cheese, black olives, muffuletta olive salad, and extra mozzarella, though. Yumm!
But, I still haven't found a pizza sauce, packaged or homemade recipe, that I really like and can "get behind" so it's a standby to always use.