One of the most classic of all toys is the yo-yo, and what better way to spice up an old favorite than by designing your own? Designing toys is also a great way to get students excited about science and engineering, and it can encourage them to express creativity in new ways. (Note: Final product not intended for use by children)

If you’re a teacher, this project is a great vehicle by which to teach students some of the principles of science and design thinking. More specifically, designing a rocket can be a great way to push students to gain a better understanding of potential and kinetic energy. For a video on the topics of potential and kinetic energy within design thinking, click here. You can also find a complete lesson plan devoted to these topics, as well as instructional materials like learning objectives, test materials, and evaluation rubrics here.

Step 1: Download Autodesk 123D Design

Before you start, download and install Autodesk 123D Design (it’s totally free). 123D Design makes it easy to manipulate all kinds of shapes and create viable designs using numerous materials. For a general tour of the interface and commands, see these short tutorials:

Step 2: Model One Side of Your Yo-Yo

Using the sketch>polyline tool, draw the profile of one side of your yo-yo. Once you have closed off the profile, it should change color.

Using the sketch>fillet tool, round off the rough edges on your profile. You can then adjust your model as necessary by moving control points. For a step-by-step video tutorial on this stage, see the video below.

Step 3: Model the Yo-Yo Body

Go to the home view, select the profile you created, and select revolve. Select the axis of revolution, and enter 360 degrees for a full revolution. If you turn off the sketch, your design should look an awful lot like half a yo-yo.

Since the two halves of the yo-yo will require some type of connector, you should model that pin. Create the diameter of your pin on the center of your half yo-yo using the sketch>circle tool.

Rotate the sketch to the front view, and extrude the pin beyond the left hand edge. Be sure to select “new solid” to create a pin, rather than just a hole in the middle of your yo-yo. You can soften the edges on the pin with the modify>fillet tool.

From the pattern menu, select “mirror.” Select the body and the pin, then select the mirror plane—the face of the pin—to show the mirror preview. Apart from colors and materials, your design should look an awful lot like a yo-yo at this point. For a step-by-step video tutorial on this stage, see the tutorial below.

Step 4: Customize Your Yo-Yo

Now comes the fun part—customization! Sure, you did already design a custom shape for your yo-yo, but this is the point in the process where you really get to give this toy some personality. To add material, select a face or faces, choose a material, and apply it.

Finally, turn the whole thing into one item by selecting all the faces and grouping them. Be sure to save the file. For a step-by-step video tutorial on this stage, see the video below.

Step 5: Print!

In order to print parts from 123D on your MakerBot you will need to install the Autodesk 3D Print Utility which will prepare your parts for printing. For more information on the Autodesk 3D Print Utility click here.

You will also need to download and install the latest version of the Makerware™ software from MakerBot. The software is free of charge and can be downloaded here.

Once a part has been created and is ready for printing you can select 3D Print option from the 123D Menu. This will bring up the 3D printer dialog where you can select your printer and options for printing.

After setting up your printer options, you will be given the choice to save as a .stl file or send directly to the Makerware software for printing.

If your printer is not listed in the Autodesk 3D Print Utility, you can still export to a .stl file directly. This will allow you to use any software your printer requires. This can be done by selecting the Export STL option from the 123D Design menu.

Lastly, if you don’t have a 3D printer, places like TechShop have the tools to turn your design files into physical objects, and staff the people who can show you how. Places like Shapeways can even print them for you.