Draw the Shape That Solves the Problem
Atlas the friendly fox stands at a bright wooden table, holding a big orange crayon and pointing to a drawing of a wide flat bridge that connects two tall stacks of blocks, showing how the shape must be long and flat to reach across the gap.
- Explain that the shape of a drawing shows how an object will work.
- Match a problem to a shape that can solve it.
- Draw a simple shape and say what job that shape does.
- Identify why changing a shape in a drawing is easier than fixing the built object.
Key terms
- shape
- the outline or form of an object that decides what it can do
- drawing
- a picture on paper that shows your idea before you build it
- plan
- a drawing that shows the shape you will build to solve a problem
- gap
- an open space between two things that something must reach across
Shape Decides What It Can Do
The shape of a thing decides what job it can do. A tall thin tower reaches up high, so it is good for holding a flag. A wide flat shape stretches across, so it is good for a bridge over a gap. A round shape rolls, so it is good for a wheel. If you pick the wrong shape, the job will not work. That is why engineers think carefully about shape before they build anything.
Why Drawing First Is Smart
Drawing your idea on paper first is a clever trick engineers use. On paper, you can look at the shape and ask if it will really do the job. If it is wrong, you fix it with one stroke of a crayon. But if you build the wrong shape first, fixing it means taking the whole thing apart. Drawing first lets you catch mistakes early, when they are quick and easy to change.
Worked examples
Mia needs to reach across a wide puddle. What shape should she draw, and why?
- Name the problem: she must reach across a gap, not go up high.
- Think about which shape stretches sideways across a gap.
- Pick a long flat shape, because it can stretch from one side to the other.
- Draw the long flat shape on paper and check that it reaches across.
Answer: Mia should draw a long flat shape, because a flat shape reaches across a gap while a tall shape only goes up.
Activity
Put these engineering steps in the right order from first to last.
Practice
Draw two different shapes and write one job each shape could do.
Pick a problem like crossing a stream, then draw the shape that solves it.
Common mistakes to avoid
- The shape does not matter as long as you build something.The shape decides what the object can do, so the wrong shape will not solve the problem.
- You can just remember the plan in your head.Drawing the shape lets you spot problems and fix them on paper before you build.
Check your understanding
Mia wants to build something that reaches across a puddle. What should she draw first?
Why do engineers draw the shape of their idea before they build it?
Sam draws a tall thin shape for a bridge. He builds it, but it does not reach across. What should Sam do next time?
Recap
The shape of what you build decides what it can do, so engineers draw the shape first. On paper you can check if a shape will work and change it with one crayon stroke, which is much easier than fixing a built object. Think about the problem, draw a matching shape, then build.
Reflect
Why is it easier to change a shape on paper than after you build it?