The Difference Between the Men and the Boys....
The next step for young inventors, should be hand tools. The first should be safety glasses and ear muffs, as they will protect young eyes and ears from the hazards of most traditional manufacturing shops (as they move up from hammers to saws to whatever), and since that is the eventual goal of these young inventors, this is a good thing.
The advent of affordable 3D printers has made prototyping for boys (and girls) easier than ever. This might be a good goal for the young, and the not so young as well.
The difference between the men and the boys is not only the price, but often the size of their toys. Joinery takes on a smaller dimension when it comes to toy making, but the techniques are still the same. Some friends of mine found a toy house and asked if I could build one for them. The molding of the wood was fairly straight forward, and the joinery? It was simple dowel joinery. Toy kitchens made of wood reflect the same cabinetry skills used in the real thing. Doll houses typically follow similar structures and methods used to build a full sized house.
The toys children play with often have excellent examples of joinery methods. A good example is the jigsaw puzzle. It covers many different kinds of joinery. Round the edges on a dove tail joint and you have the basic shape for a puzzle. Add a few butt joints and tongue in groove and the rest of the components are covered. Then there is the model of the real thing. Toys like Lincoln Logs, Legos, and Tinker toys give children from ages 3 to 103 the ability to visualize any structure in three dimensions. Not only that, they can demonstrate imaginative joinery that may be used in conventional construction in the future.
At one time we were drawing the plans for a house we hoped to build, and our children had been playing with the Legos. We began putting walls up and decided that it would be nice to be able to see the house in three dimensions. A few days, and an extra box of Legos later, we had a fairly close model of that house.
Toys are not the only source for examples of joinery. Crafters regularly toll paint wood pieces that show traditional as well as innovative forms of joinery. In another area, it is not uncommon for engineering and manufacturing companies to build scale models of structures for testing, as well as for showing clients and other parties, how a completed project will work. These models use great detail to demonstrate that the actual structure will be sound. I have also worked on a project where a model was used to see why the full sized version failed. The availability of miniatures makes this all the easier for the home builder, and after the actual project is complete, most children would love to have a model of their own house to play with.
So get out the jigsaw puzzles, and review the various types of joinery represented there, and then play with the rest of the toys that you played with for years. The difference between the men and the boys is the size of their toys.