Riding an ATV that's too big for you is usually not a good idea. There are several key points you should take into consideration if you've never ridden, and the size of the ATV is one of the most important. 
Size is especially important when you're a parent who is considering buying a youth ATV. Since ATVs can be dangerous, especially for young or in-experienced riders, its important to know how to ride safely and to ensure your kids are riding something appropriate for their size and strength. And yes, that means you shouldn't put a 14 year old 150 pound kid on a little 50cc quad built for a 60 pound 7 year old.
If your kids visit with friends who have ATVs you make sure the friend's parents know your feelings about them, what ever they are. If you're OK with letting them ride, make sure to pack their ATV safety gear.
Find out more about why size matters on an ATV when it comes to strength and weight.
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