Now that you have a mad TinkerCAD skillage, you will need to find something to use as a guide online and then propose a final project in TinkerCAD.
Choose something that is NOT super simple and you will be done in 15 minutes, but something that will challenge your CAD skills and maybe take 2 or 3 class periods.
You need to have a tutorial to follow and will turn in the link with your project
Below are some links you can peruse, but you are free to find something on your own. When you search include the word "tinkerCAD" in your search.
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