Drink more water!
We all should drink 64oz of hydrating liquids each day (caffeine and alcohol don't count). Water is the best choice.
You should drink more if you exercise to the point of sweating (weigh yourself before and after you exercise and drink the difference (if you lost 1lb during exercise, drink 16oz of water)).
Now that the lovely summer humidity is starting, make sure you and your kids drink even more. We like to have re-useable water bottles for each kid and make sure they drink throughout the day.