I agree that older snakes are way more tolerant than younger ones... especially if those snakes have been handled all of their lives, and they realize that humans are not a threat.
I have to disagree about the wanting to get away though... corn snakes are hyperactive when they are out. It's impossible to tell if they are stressed or just curious. It's a bit more obvious with calmer snakes (Like my BCC or kenyans.. if they move at ALL, I know they are stressed, hehehe).
Nonetheless, 10 or so minutes a day should be more than enough time for the kids and for the snakes to get their exercise.
- Ken LePage