I'm of the firm opinion that every child should be involved in some sort of physical activity. It teaches them coordination, resilience, how to listen and learn, and how to cooperate and communicate with others, particularly with their peers.
And I might be biased, but I think there's no better activity to get your little girl or boy involved in than Brazilian Jiu Jitsu. Here are some tips for getting your kid started in BJJ:
Getting Them to Try It
Unless they already have a little jiu jitsu friend whose been telling them all about how awesome it is, it may be a little difficult to get your child to step on the mat for the first time. It's kind of like going to a new school where he/she doesn't know anyone... it's scary! The best way to get your child interested in the first place is to go with your child to visit a local jiu jitsu academy during the kid's class. Have him/her meet the professor or coach before the class starts - usually he/she will introduce your little tyke to some of the kids who regularly attend - then have him/her watch some or all of the class. Seeing all the other kids have fun and interact with each other will ease any fears your child might have, and get him/her excited to participate in the fun next time! Plus, having him/her see how the class is run, will allow him/her to be more comfortable participating in the class, as the setting and structure will be more familiar.
Finding the Right Academy
Of course, that's assuming you've already found an academy you like! A lot of kids these days start jiu jitsu because they have a family member - a mom, dad, uncle, aunt, cousin, etc. - who does it. So naturally, they go to their family member's gym. But if that's not your case, you'll want to find the perfect academy for your little guy or girl. As popular as jiu jitsu is becoming, odds are there's a BJJ gym or academy near where you live, work or where your kid goes to school. There are very, very few academies that don't have a kid's class. So that's good news. However, just as you wouldn't go to just any gym yourself, you should also make sure your child's academy will be a good fit for him/her. So do your research... Does the kid's instructor seem friendly and knowledgeable? What do the other parents say about the class? Is there a good number of children around the same size as yours? Do the other kids appear to be respectful toward the coach and do they appear to be learning?
Getting Them Geared Up
Once you've found the right spot for your little dude/dudette, you'll have to get all the right gear for him/her. First and foremost... find a nice, durable gi that fits. Many academies have a small selection of kid's gis available for rent or purchase at the academy, but many more do not. Regardless, especially if your child sticks with jiu jitsu for the long term, he/she will need many more gis in the future. Here are a few kid's gis that we like, many of which come with a free white belt (some don't, so make sure before you buy, in case you'll have to buy the belt separate!). But don't just take our word for it. Do your research. Check out the sizing charts on each gi model to see if your child fits better within a certain range. Have your child try on some of the other kids' gis before or after class to check the fit. While the gi might be the most important element, he/she will also need a rash guard and maybe some shorts and/or spats. You might also want to invest in a kid's mouth guard, too. Jiu jitsu doesn't involve any striking, but there's always risk of being hit by an errant elbow or knee.
Last, but definitely not least... how involved should you be as a parent? If you already do jiu jitsu, you're ahead of the game. As you progress, you can help your child at home. Just take care that you're not over working your child in a way that makes jiu jitsu a job instead of the fun, totally awesome activity that it is, thereby resulting in "burn out". I've seen this happen far too often. If you don't train, I highly encourage that you step on the mat a few times at least, just to experience a little bit of what your child might be going through. Why? Because too many parents who don't train try to "coach" their child, usually by yelling at them. If you've never been on the mat before, let their coach do all the coaching... that's what he/she is there for. Otherwise, you're going to risk frustrating your child, putting too much pressure on him/her, and looking like an ass as you do so. Just sit back and watch your child grow. That or go somewhere else. Go run errands, take a nap, whatever.
It's almost always a guarantee that your child will absolutely fall in love with jiu jitsu once he/she steps on the mat for the first time. If not, that's okay, too. Jiu jitsu is not for everyone, and there are plenty of activities in the world that he/she will excel at instead. The most important thing is that he/she is involved in something that allows him/her to see the tremendous potential he/she has.
Train on... Oss.