Most everyone has seen a digital printer that uses ink to print words and pictures on paper. Lots of people even have a printer at home. You can draw a toy with a graphics program on your computer, and then on paper with a normal printer, print the toy you drew. That toy printed on paper will look flat. It will have length and width but no depth because the drawing was printed in just two dimensions.
Now there a printers that can print with length and width and dept. These are called three dimensional (3D) printers. These printers don't print on paper, but instead use plastic, chocolate, sugar, metal, ceramics and many other materials to form a shape, usually layer by layer. Those shapes can be anything from a sugar flower to spare parts for a car. People who work all the time with 3D printers say, “If you can draw it, you can make it with a 3D printer.”
If you would like to learn how to make drawings that would be the designs for the toys you imagine, which could be printed by a 3D printer, try the free online tutorial at http://www.shapeways.com/tutorials/introduction-to-3d-design-printing-for-kids. In this 3D printing and modeling course, kids learn how to design their own robot for 3D printing! The course uses a software tool called, “Blender,” a professional-level, open-source 3D modeling software, working with shapes to create a 3D model of a robot.
If you have a smartphone, you can also try a free 3D design app from Autodesk for iOS, Android or Windows. Called, “Tinkerplay,” the app was created so that kids of all ages can creatively play through 3D design and 3D printing. The Tinkerplay app allows users to design and customize characters and creatures digitally, with the option to 3D print afterwards. The 3D printed parts can be snapped together to make toys that are much larger than what 3D printing alone currently allows. The Tinkerplay app lets users quickly get started by dragging and dropping interchangeable parts to make custom creations. Learn more about the app at www.123dapp.com/tinkerplay