Elastic Launched Gliders is perhaps the easiest flight event to do without a kit. Few materials involved and few pieces to cut, maybe just a lot of sanding. I encourage you to try making one with balsa sheets (for the wings and stabilizer) and balsa sticks (for the fuselage). For your launch handle, you can attach leftover Wright Stuff rubber to a dowel. There are many guides out there for making and testing gliders, and you're always welcome to ask any questions on forums.
"One of the ways that I believe people express their appreciation to the rest of humanity is to make something wonderful and put it out there."