Our elementary school encourages kids to bring their own water bottles to school. It keeps them well hydrated and eliminates the need for repeated interruptions when 20 kids in the class have just returned from gym or recess or... well... at just about anytime of day really.
To prevent the water bottles from 'sweating' a puddle all over their desks, the parents are asked to cover the water bottles with a sock.
I have also put socks around water bottles to carry in a tote/gym bag or in my purse.
Water bottle socks works for me!
For more tips, visit Rocks in My Dryer.