Hey there potential Airsofter parent! First I'd like to thank you for taking the time to look into things for your son(s) or daughter(s). It may be of value for you to know I am also a parent. A few concerns I have heard that I would like to address are safety gear, general equipment, costs, behavior and motivation.
Safety gear is comprised of three parts, equipment, commitment and experimentation. What this means is each piece of protective gear is an experiment that may or may not work. However some kids will resist using helmets or pads because it's "uncool." Only you as their parent can spot resistance and lack of commitment to safety over problematic gear. The good news is there are only 2 pieces of vital safety gear that may cause this issue, a face mask and full seal ANSI Z87.1 / CSA Z94.3 rated goggles.
Goggles can be a legitimate problem. Fogging is common and while you can buy fancy goggles with fans the best solution is very simple. Remove any foam from the vents and then before each game put a drop of dish soap on each lens and buff it until clear. It's cheaper and less harmful than chemical anti fog wipes and will help ensure your child or children use their eye protection rather than complain about it or take it off in a dangerous situation.
Face masks can also be problematic. Often times the smaller ones are best. Just something to protect your teeth. The larger ones with ear and throat protection often cause problems with aim and can dislodge your eye protection which is a bad situation when you are being shot at. If you are concerned about ear and throat protection a decent option is a shemagh for the throat and the goggle straps will often cover and protect the ear canal. There are many other options but these are simply recommendations and you're free to experiment.
General equipment and cost go hand in hand and is always a big issue with kids trying new things. For years I saw kids learning guitar being set up for failure by parents unwilling to buy quality gear. Parents feared anything they bought their child would end up in the closet collecting dust after a month so they buy cheap. This is sabotage at its finest. If you buy a good guitar and amp it will have a far better chance of inspiring your child to continue learning. If you find they lack the real dedication to continue a good guitar and amp will retain its resale value unlike cheap entry level gear. Airsoft is no different. Buying your kids cheap "crap" for fear it will collect dust helps ensure that is what will happen. You can buy decent stuff for around $300-$400 to get them started and build from there. $300-$400 is incredibly cheap compared to most other contact sports with Hockey and Football often costing thousands a year. A solid foundation can be built upon as gear and guns can be upgraded and improved if they stick with it.
Not everything is easy when kids are getting into things and there is a caveat to the affordable solid foundation I mentioned. Much like my guitar analogy they might kick and scream for the $3000 guitar they see all their favorite bands playing. The same goes for guns, their favorite gun in Call of Duty or Battlefield might be a real bank buster or simply unobtainable in Canada. This doesn't negate buying something decent just because they can't have a $500 ICS XM8 or a $1400 tricked out M14 EBR with $800 worth of optics. Buy something good, something universal so it's easily fixed and upgraded like an AK or AR15/M4 and tell them they get better guns as they level up like in a video game. Play for 6 months get one perk point. Play for a year, unlock a new gun. Be creative, speak to them on their level. Airsoft is a great activity for kids to learn personal responsibility and to give them goals. If they have to get a summer job to save up for that gun they want they will have a constructive direction and goals.
Last but not least behavior and motivation. Some people think kids who like guns are problem children training to be mass murderers or something crazy but this is just nonsense. Guns have become demonized in western culture over the last 10+ years but generations before played with guns, swords, knives, bows and history shows people are simply people with varied interests for their own personal reasons and our children are no different. Being interested in guns, shooting or hunting is not an indication of a troubled youth but rather common activities and themes known throughout human history. Many kids are interested in Airsoft due to FPS (First Person Shooter) games such as Battlefield, Call of Duty, Halo or Counter Strike. Airsoft is far better though as it teaches real world skills, gives kids goals, teaches responsibility and accountability, builds friendships and keeps players physically active.
If you have any other questions feel free to contact me
and I'll be glad to help you out.