Lesson 2: Plotting Shapes
You will explore the challenges of communicating how to draw with shapes and use a tool that introduces how this problem is approached in Game Lab. You will explore a Game Lab tool that allows you to interactively place shapes on Game Lab’s 400 by 400 grid.
Students will be able to:
- Reason about locations on the Game Lab coordinate grid
- Communicate how to draw an image in Game Lab, accounting for shape position, color, and order
Warm Up (10 min)
Communicating Drawing Information
We saw a lot of different programs yesterday, and you started to think about what types you might want to create. When we create a program, one of the things we need to do is draw everything on the screen. We’re going to try that with a “student” computer today.
One or two volunteers come to the front of the room and act as “computers” for the activity. They should sit with their backs to the board so that they cannot see what is being projected. Give each volunteer a blank sheet of paper.
Display: Project Sample Shape Drawing – Exemplar where it can be seen by the class.
You will need to explain to our “computer” how to draw the picture. In the end, we’ll compare the drawing to the actual picture.
Give the students a minute or two to describe the drawing as the students at the front of the room try to draw it. After one minute, stop them and allow the students to compare both pictures.
Prompt: What are the different “challenges” or problems we’re going to need to solve in order to successfully communicate these kinds of drawings?
There were several challenges we needed to solve in this activity. We need to be able to clearly communicate position, color, and order of the shapes. We’re going to start exploring how to solve this problem.
Activity (35 min)
Drawing with a Computer
Group: Get with a partner
Transition: One member of each group open a laptop and go to the contents for this lesson. There is a single level with a Game Lab tool.
Prompt: Working with your partner take two or three minutes to figure out how this tool works. Afterwards be ready to share as a class.
Location of the Origin: The origin of this grid, as well as the origin in Game Lab, lies at the top left corner. This reflects the fact that documents tend to start at the top left, and ensures that every point on the plane has positive coordinates.
Distribute: Get an activity guide. Be sure that one student (Student A) receives Version A and the other student (Student B) receives the Version B. DO NOT look at each other’s papers.
Set Up: In this activity, you will try to recreate images based on a partner’s directions. The student who is drawing will use the shape drawing tool on Game Lab to draw the shapes. Students should keep their drawings hidden from one another throughout the activity. While completing a drawing the instruction giver should also not be able to see the computer screen.
Drawing 1: Each member of the pair should complete their first drawing, taking turns giving instructions and using the tool.
Drawing 2: Each member of the pair should describe their second drawing to their partner.
Draw Your Own: If time allows, create your own drawing to communicate to your partner.
When we make images, we need a way to communicate exactly where each shape goes. The coordinate plane helps us to do that. Our coordinate plane has two coordinates, x and y. The x-coordinate tells us how far our shape is from the left of the grid. The y-coordinate tells us how far our shape is from the top of the grid. The black dots on the shapes help you be very specific about how the shape is placed on the grid.
Wrap Up (5 min)
Journal: Have students reflect on each of the following prompts
- What things were important in communicating about position, color, and order of the shapes in this activity?
- What’s a way you have seen similar problems solved in the past?
At the beginning of class we saw that communicating how to draw even simple shapes can be pretty challenging. The grid we learned about today is one solution to this problem but there are many others that could’ve worked. In fact a lot of you probably noticed that the grid in Game Lab is “flipped”. Computer screens come in all different shapes and sizes, as does the content we show on them. We need to agree on one point where all the content can grow from. Since we read starting at the top left corner, the grid on a computer screen starts at the top left corner as well. There’s also the benefit of not having to use any negative numbers to talk about locations on the screen. Don’t worry if this flipped grid is a little tricky still. We’ll have plenty more time to work on it in coming lessons.