He hasn't yet figured out that it screws off but I think that even when he does, he will have a hard time doing it because it's really secure and sturdy
My son has thrown this snack cup numerous times and it has held up well
my son will pull out puff by himself I have one of these cups and my twins fight over this one
With toddlers there is not much they won't destroy but this is definitely a cup that will hold up
She figured out in about a day that she could pry the lids off those cups with her teeth and the proceed to dump the crackers all over the floor, car, etc
We love this snack cup in the car, the floor and car seat stay clean