BlocksCAD is a free online software designed to teach students coding and Computer Aided Design. Using BlocksCAD, students will design a 3D Earphone Holder. Using shapes, text, translate and difference, students will be exposed to computational thinking to construct something they can 3D print!
The Earphone Holder Activity is best for 5th - 8th grade for students with basic BlocksCAD experience.
As a Teacher you can create a free trial of our BlocksCAD for Education platform. From here you can create classes with unique join codes and manage student work.
Overview and Background
Students will become familiar with using the difference set operation block with which they will subtract shapes and text from a solid shape on BlocksCAD. Difference is a useful tool for partly/completely cutting out shapes or text from solid shapes. Learning the difference skill will expand the students capability to create more complicated structures and designs on BlocksCAD.
Lesson Plan and Activity
REVIEW / PRIOR KNOWLEDGE
In this lesson, basic prior knowledge of BlocksCAD is optimal, students should have a basic knowledge of how to create 3D shapes and translate them along the coordinate system.
● Shapes and Translation: Caterpillar, Fancy Cube, Project Robot, Snowman, Top
Skills and Knowledge
● Experience creating 3D shapes on BlocksCAD.
● Understanding of 3D grid coordinates by translating objects along the X, Y, and Z axes.
● Emergent understanding of 3D space, including directions like forwards, backwards, sideways, and up and down.
● Understanding of positive and negative numbers by positioning shapes at positive and negative coordinates on the 3D grid.
● Students will construct models using basic shapes on BlocksCAD.
● Students will learn how to subtract shapes and text from solid shapes using difference.
Mini Lesson (I Do)
In this sequence, students will learn how to use the Set Operations (sometimes called Boolean Operations), starting with Difference. Set operations will allow students to create new and unique shapes, and to modify the default shapes of BlocksCAD into practically an infinite variety of shape combinations. Unlike transformations, which make changes to individual shapes, the set operations are all about combining multiple shapes together.
Begin by showing students examples of the work they have done so far using translation, rotation, and combinations of the two. After reviewing the variety of models students have made so far, you may ask students if they can think of shapes they still cannot make in BlocksCAD. Record student ideas. Some answers could include parallelograms, prisms, shapes with a specific number of sides (e.g. hexagons), pyramids, tubes, hemispheres, and more. Discuss some of these options as they are suggested, to see if students have creative solutions for how to make these shapes using the tools they know.
Conclude the discussion by telling students that today they will learn how to use a block which lets them "subtract" or "cut away" one shape from another. While they may not be able to use it to make every shape they listed, it will allow them to vastly expand the variety of shapes they can make. This includes being able to cut shapes in half (or any number of slices), and being able to put holes through shapes.
Guided Practice (We Do)
This lesson should be taught after students feel comfortable creating 3D shapes and translating them on BlocksCAD.
Have students follow along with you as you demonstrate the following actions in BlocksCAD:
Introduce “Difference” in the Set Operations tab:
- Get a sphere and a cube and show what happens when you do sphere minus cube.
- Ask what do you think will happen when you do cube minus sphere?
-Explain that the order makes a difference just like in math:
5-2=3 but 2-5≠3.
-Now show a sphere and centered cube. The sphere will overlap the cube so disable the sphere in order to show that the cube is really there.
-Then do sphere minus cube.
-Ask what just happened?
-It did subtract the cube but we can’t see it unless we zoom in!
-Explain that when using difference we should first get the shapes arranged and then do the difference.
-Demonstrate using difference with different colored shapes. The cut off is more clear this way.
-Demonstrate that Difference is a good way to figure out if two shapes are touching each other. Get a sphere and a cube to the point where its hard to tell if they're touching or not and use the difference block to figure it out.
Independent Practice (You Do)
Give students one of the onesheets for Difference (Earphone Holder) and allow them to complete their own version of the project (changing the solid shape, text and color). Emphasize that students do not need to make their models exactly like the photo, and that you will not give them any number values for their shapes. Instead, if they would like to print their badges, give them measuring tape and guide them through the process to create the holder in the right dimensions and measurements to fit their earphones and not making them too thin. Act as a mobile facilitator to answer students questions about how to change the dimensions of basic shapes to fit the measurements and using the Difference block. Students who finish early should try the addition models in the Now Try This! section, or can work on an additional One-sheet, or their own creations.
If you have a BlocksCAD for Education account or free trial it is easy for you to manage student work.
Alternatively, students can create projects without an account. Once completed they can save the "Blocks" file to their computer by going to Project -> Save Blocks to your computer. If you want to print the file out you or the student can click "Generate STL" in the render window. This is the printable STL file.
An STL file cannot be turned back into Blocks to be edited, which is why you may want to save the Blocks file as well.
● One-sheets: Earphone Holder Activity
● Computer with a browser
● Measuring Tape