I do recommend that you use mouthwash regularly on a daily basis once to twice a year after you brush your teeth. I also recommend to my patiences that they use mouthwash with no alcohol in it. What I suggest that kids use is ACT, you can find this brand at your regular supermarket or drugstore. This mouthwash has fluorine in it, and is available for kids and adults in a variety of presentations.
If you are looking for mouthwash look for one that has no alcohol in it, and one that has fluorine in it, so you can use it in an early basis after you brush your teeth, rinse out, you can switch for thirty seconds and then spit out. This will improve the health of your teeth and will also prevent cavities.
Stay tuned for more tips to maintain healthy smile and strong teeth!