Build an "electric" Cub-O-Matic machine into which Tiger Cubs entered, were "cooked", and then exited as a Cub (yellow neckerchief on).
To make this machine, obtain a large cardboard (appliance) box. It can be open at the top and bottom, but may need to be reinforced with small boards to help it keep its shape. Paint it half orange and half blue.
Fashion a door on the front of the box by making cuts that will be the top and the handle-edge of the door. Then make the "hinged" side by folding the door back so it can swing open (i.e. the hinges are really just part of the box front). We didn’t make the door the whole width of the front side. Add a simple handle on the outside that attaches to a Popsicle stick on the inside that will "catch" when turned - to keep the door closed.
On the back of the box, about shoulder high, cut a one-foot square door, making the hinge in the same way as the front door (side hinged is probably easier to work with than top or bottom hinged) - don’t cut a hole out. This is the "trap" door that’s used to put the scarf on the Tiger cub.
For effect, we added a "done-ness" dial on front which didn’t turn: it had Tiger and the other Cub ranks on it. A black arrow-shaped "pointer" was attached to a dowel that extended through the done-ness dial to the back of the box. There was also a light bulb on front, whose cord had a toggle switch placed in back of the box.
For the ceremony, the Cubmaster explains that the Tigers are ready to graduate to the next rank, and to facilitate this process, he’s using this handy-dandy, state-of-the-art Cub-O-Matic machine. He must choose the desired setting (i.e. Bobcat), insert a Tiger cub, and let him "cook" until done. To alleviate any fears or apprehensions, the Cubmaster shows that he can enter the Cub-O-Matic, get "cooked" and come out unscathed. (Our Cubmaster entered the box in regular uniform and came out with a clown’s wig & nose on. Upon exit, he pretended to not notice the changes!)
Only one boy can enter at a time. The audience can’t see the person(s) in back of the box who attaches the yellow scarf & slide on the Scout, turns the done-ness pointer, then when "done" turns on the light.
Our boys were leery at first, but the Cubmaster’s act helped ease their anxiety. After the pack meeting, all the Cubs wanted a turn in the Cub-O-Matic!