Encouraging children to read books and learn what has been written about animals is always good. The internet is a good resource too though not everything on every website is correct and there will be variations as many people have slightly different methods to ensure an animal meets its needs.
For corn snakes there really isn't any need to have bright lights in their cage to observe them moving about during the evenings. Corn snakes are more dusk/dawn active, than full nocturnal and any clear sided container/tank will allow people to observe them moving about.
Short handling times are also good to get a feel of how snakes move and explore their environment. Observing them feed is good as well (still best to use frozen thawed though...most corns will strike and coil a frozen thawed mouse dangling on tongs to give it movement. Even when the snake strikes and starts to coil, wiggle the mouse still which will encourage the snake to coil tighter to subdue their prey. Unless you have a lazy corn like I do...she won't coil at all, or very little..just grabs the rodent and starts eating it, even if I wiggle it. The one time I decide to feed a live rat fuzzy...she didn't really coil around it...just tried to eat it live...after a minute of hearing the poor thing squeak in protest I used pliers to sever the spinal cord...and never fed live to her again. She's just not good at killing. (though I wonder if its partly due to her particular genetics, I think she's rather inbred as she's smaller than most corn snakes (though still in the range cornsnakes can be in, at just a little over 3' long. Either way I have personally decided not to breed her, and just keep her as a pet.)
Weighing and measuring the length of your snakes can be an experience as well. Recording days fed etc. is a good way to teach kids how keeping track of bi-weekly or monthly growth compared to amount of food fed (could weigh prey items as well) will teach importance of accurately recording data. You can even put the weight and growth changes in a graph using MS Word or other similar program (I think Excel allows the creation of graphs) or just doing it on paper.
Youtube has all kinds of educational videos on corns and other species..such as how to properly sex snakes using the 'popping' method or 'probing'. Though be aware that there are alot of crazy stuff people put on youtube...such as feeding live, or feeding anything that can be tossed into the cage...often inappropriate to dangerous to feed things.
websites like this one and www.reptilechannel.com and many others, have tons of general information about many species. (the Reptile channel also has a kids section with games and stuff...and downloadable images to color...) Doing a google search on education reptiles may bring up other activities one can do with their children.
Buying books of your local reptiles and taking your kids out to find them is also another great activity. Joining a local reptile club and going to meetings/events with your children is another way to expose them to herps and give them the opportunity to talk to other reptile enthusiasts. It is also a great way to network and you may find out there is more available about reptiles in your area than you currently realize.
With alot of big bills being proposed to restrict or outright ban the keeping of various reptiles, it would be beneficial to teach your kids how such laws can be very harmful and most are based on very little fact, and are fear driven (or purely money driven). Have your children write letters to your congressmen etc...asking not to ban larger snakes (these snakes are no where near as dangerous or environmentally impacting than a feral cat or dog, and often no more dangerous to young children than out of control dogs.)
Plenty of things to teach children...even something as simple as to not approach a strange animal and always handle animals with care. Being observant to the warning signs in animals is also very important, even with small snakes. A snake drawing back his head and forming a 'S' with its neck is a classic sign of uncertainty and fear in a snake. It is going into a defensive posture. It may not bite even if picked up but knowing its being defensive is a good time to approach more slowly or just give it a moment to relax, if you opened the cage or removed a hide suddenly. With corn snakes the vibrating tail (corns and many colubrids do this to imitate the sound of a rattle snake's rattle to scare off a potential threat. Against dry leaves or even the side of a plastic cage, the sound of the vibrating tail is pretty close to that of a rattle snake.
One thing you could try is ask your children if they could have any reptile or any animal in the world...what would they choose to have? Have them research it online (with supervision of course) and write down everything they need to care for it (what kind of food it eats. How big the animal gets, how big of a cage would it need. etc.) Depending on what they choose as their 'dream' animal they may realize (maybe with guidance from you) how difficult it would be to keep that animal.
I know for myself, when I decided I wanted to buy a reptile as a pet...many years ago now. I wanted a green iguana. I had always thought they were fascinating and get so big and seem so calm etc. But after spending some time researching, I realize there is alot more to properly caring for a green iguana than just a cage and giving it food. I knew they grew large but I didn't think much about big a cage they really needed, or the special heating/lighting. The diet though not difficult in itself, but adding the fact they need very nutritious greens, vegetables and fruit and fed quite a variety daily, plus giving supplements etc. would also be a challenge. (at the time where I lived, didn't think I could find all the fancy greens recommended for green iguanas). Then I learned about their dispositions. Some are quite laid back but mature males can get very aggressive and moody around breeding season to the point they will attack males of other species (even human men) and a 5' lizard with a powerful whip like tail, jaws and claws having a bad day...seemed far too much for me, a novice reptile keeper who is only 5'3" herself.
Needless to say I settled on buying a bearded dragon as I my first reptile pet. (once I researched them thoroughly as well). Besides, I liked the idea of owning a 'dragon' (being an avid fan of mythical dragons all my life). Since then I have owned many other reptiles, from geckos and skinks to various species of snakes all of which I have enjoyed having as pets.
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PHLdyPayne