I used Bernat pipsqueak yarn to make the snowballs, they're incredibly soft and look a lot like snow. I made the snowballs decent sized, I didn't want them too tiny, with my kids they'd definitely go missing if they were too small! Some are a little bigger than others, the yarn isn't the easiest to always tell where your stitches are ending up.
I also crocheted a simple granny square bag to keep the snowballs in when they're not being thrown around.
I'm really happy with this fun kit! I think it's going to get quite a bit of use here.
There's no pattern for this but if there's interest, I will try to put together a pattern.