CAD Starter Day

Overview

Students are introduced to CAD (Computer-Aided Design), how it’s used in engineering, and how to start sketching and building in OnShape. This lesson sets the foundation for later activities where students will measure, construct, and modify 2D/3D geometry using precise inputs.

Learning intentions

• Students will be able to explain what CAD is and why engineers use it.
• Students will be able to describe OnShape as a tool for creating and sharing designs.
• Students will be able to follow step-by-step CAD instructions to make a basic part.
• Students will be able to organize ideas clearly in a short “designer reflection” using examples from the lesson.

Success criteria

• I can describe CAD and name at least two ways it is used in real engineering.
• I can navigate OnShape (open workspace, start a sketch, create a simple feature).
• I can use at least one measurement or constraint accurately (for example, a length or angle) when building a simple design.
• I can write a clear paragraph that introduces my topic and explains what I learned, using an example.

Curriculum links

• Mathematics — Geometry: Draw geometric shapes with given conditions and focus on triangles (foundational to later measured constructions).
• Mathematics — Geometry: Solve problems involving scale drawings (used later when converting measurements).
• ELA — Writing: Introduce a topic, organize ideas, and include formatting/graphics when useful.
• Mathematics — Mathematical Practice: Consider tools when solving problems and recognize limitations.

Lesson structure (45 minutes)

1. 0–5 min · Hook (Real-world CAD). Teacher shows 3 quick images or props (helmet, keychain, bridge component) and asks where CAD might appear in making each item. Students do a quick think-pair-share: “Where do you think design happens before something is built?”

2. 5–12 min · Direct teach (What CAD is + why it matters). Teacher explains CAD as a precision design tool used by engineers/manufacturers; emphasizes accuracy, iteration, and communication. Students take a 3-bullet “notes” sheet: definition, purpose, and one real-world example.

3. 12–18 min · Tool demo (OnShape overview). Teacher demonstrates OnShape basics on a projector: workspace, tabs, sketch vs. part, and saving/versioning. Students follow along on their devices in “watch mode,” then state orally one tool/button they noticed (teacher records 3–4 student observations on the board).

4. 18–30 min · Guided build (First OnShape sketch/feature). Teacher leads students through a simple, repeatable creation: start a sketch on a plane, place a rectangle or right triangle, then create a basic feature (like an extrude) using a default depth. Students complete the same steps, using a checklist; teacher circulates to verify they can (a) start a sketch, (b) constrain/lock at least one measurement (length), and (c) finish the feature.

5. 30–38 min · Mini problem (Given conditions → correct shape). Teacher gives two “challenge cards” on the board (for example: “Create a right triangle with legs that are 2 units and 3 units” or “Create a rectangle with one side twice the other”). Students choose one card and translate “given conditions” into their CAD sketch by adjusting dimensions until the sketch matches. Teacher prompts: “What changed? Why did the sketch update?”

6. 38–45 min · Exit reflection (Organizer paragraph). Teacher explains the reflection prompt and models a strong opening sentence. Students write a short paragraph using a graphic organizer sentence frame:

• Introduce: “Today I learned…”
• Explain: “CAD helps because…”
• Example: “In OnShape, I… (what I built)”
• Reflection: “Next time I will…”

Resources

• OnShape accounts or classroom-managed login access
• Projector/teacher computer with OnShape running
• Student devices (Chromebooks/laptops/tablets as available)
• Student CAD checklist (printable)
• Two “Given conditions” challenge cards (printable)
• Designer reflection worksheet with sentence frames
• Optional: headset for audio instructions and timer

Assessment

• During guided build: teacher uses a quick observation checklist (navigation, sketch start, measurement/constraint used, feature created).
• During mini problem: teacher checks that the final sketch matches the given conditions (students can explain what they adjusted).
• Exit reflection: collect the paragraph for evidence of clear topic introduction and organized ideas with an example.

Differentiation

• Support: Provide step-by-step photo directions on the checklist (Step 1 sketch, Step 2 add dimensions, Step 3 extrude). Offer a “help button” card with common troubleshooting (can’t see constraints, lines won’t lock).
• Support for EAL/SEN: Sentence frames and word bank (CAD, sketch, dimension, constrain, extrude, design). Allow oral rehearsal before writing.
• Extension: If time allows, students can try the second challenge card and add one additional constraint (for example, making a shape fully defined or adjusting depth consistently).
• Grouping: Pair students with mixed strengths; assign one “driver” and one “checker” who reads the checklist aloud.

Estimated instructional alignment notes (for teacher planning)

• The guided build and mini problem directly reinforce the habit of constructing shapes using given conditions and precise inputs, which will connect to later measured geometry constructions.
• The reflection paragraph targets clear topic introduction and organization of ideas with a relevant example, using a structured organizer to support student writing.
• The tools-based problem solving is practiced as students decide when to adjust dimensions/constraints and verify their results in OnShape.