These are just a few things I have never given up on as I've grown older. They fuel my imagination and may be the reason I still get carded...even with a beard.
Coloring: I maintain a active 96 pack of Crayola Crayons that are well worn on both ends. I have two coloring books in eye sight. There may be more but I haven't looking in the bedroom. I tend to rebel a lot and color outside the lines just to spite every teacher from Kindegarten to Thrid Grade. I also enjoy scribbling and posting them on my Fridge. Side Note: If you feel the need to "shade" you're not coloring.
Cartoons: Does anyone ever grow out of these! While my tastes have matured in animation style and context, my love of cartoons is timeless. With the help of the internet I can watch all the old and hard to find shows that I used to love to watch every Saturday morning. Like Bionic Six and M.A.S.K. so I know I'm not alone in this.
Glueing my Hands: Granted this may be an odd one but it's one that I've always liked. I just pour a bit of glue on my hands, smooth it out and let it dry. I have fun touching every day objects with my new "skin" and then trying to peel it all off in on full piece. It takes skill but it makes me feel like a snake shedding it's skin.
Slinkies: No matter where I see one, the O.C.D. Child in me has to slink it back and fourth really fast a couple of times. Gotta make sure it works right?? I've never been able to do the Ace Ventura 2 trick but I have a master plan for the Mayan Temples and a glow in the dark Slinky. Muhahaha!
Legos: I may not be too proud of how I play with these but I have been known to take over my Nephew's building plans a time or two. It's not totally wrong if I tell myself I'm teaching him....right?
Forts: I still make Forts out of sheets and protect it from my dog/dragon which we team up eventually to take out the Fan of DOOM!
Play-Doh: Maybe it's the smell or the simple hope that I might actually be a genius sculptor one day but I can never pass up the chance to shape my delusions in brightly colored clay-like substances.
Imagination: I saved the best for last. I constantly try to imagine impossible things/situations or random questions to confuse cops. Creating my own language is a work in progress. I have been to other worlds far from Earth and Conqured many worlds. I've used my secret powers to save the planet on many occasions. I also conduct interviews and Press Confrences in bathroom mirrors. I like to think that exercising my imagination leads to a healthy dream world. But I do fight a lot of Zombies in there so who really knows.
The point is no matter how old you get, you never have to truly "grow up." Even if the Doctors take your bed away because you constantly jump on it and make you wear your "magic" cloak!