I've looked at those, Teacher and one is definitely on my wish life. Just not in my budget right now.

Picked up a Pristine Pioneer filter straw for my son today. I figure it's the easiest method for him. Water tabs are something I don't think he's ready for yet. (He's nine yo with ADHD.) This way, all he has to do is pre-filter water with a bandana, into his water bottle and let it sit for a while to settle. Then he can drink it with his straw or, if he has/we have one, he can use a fire to boil the water before using his filter straw. We're going to practice tomorrow. It's a pretty simple piece of business, just like my Frontier straw, but better to practice with and get familiar with it before he needs it.

http://www.frontlinewater.com/products/pristine-pioneer-filter

Thanks for all your help guys!