Students will develop knowledge of sequential command execution through an interactive activity involving drawing instructions.

Alaska Computer Science Standards

3.AP.A.01 Create and follow algorithms to accomplish a simple task or solve a simple problem 

5.AP.A.01 Compare and refine multiple algorithms for the same task and determine which is the most appropriate.

5.AP.PD.01 Define the concept of abstraction and create increasingly complex programs. 

7.AP.A.01 Select and modify an existing algorithm in natural language or pseudocode to solve complex problems.

7.AP.PD.01 Seek and incorporate feedback from team members and users to refine a solution to a problem.

• Blank (printer) paper (qty. 5) and pencil

Lesson One (Time: 45 minutes)

• Opening Questions: "How do computers think?" and  "What happens when you are playing a video game?"

  • Allow time for students to discuss possible answers to this question. Allow for the discussion to move towards the concept of user inputs.

• Explain to students that computers operate through a series of commands, going in order, or sequentially. The language used when telling the computer what to do needs to be exact, and if it is incorrect, the output will not be what is intended. In other words, the output will be erroneous.

• Hand out a single sheet of paper to each student and explain to them that they will follow along with a set of instructions, drawing exactly as the directions state. Students should not discuss their drawing, nor look at each other's work until told to (flip over their papers when finished).

• On the board, an example set of instructions is presented to the classroom, stated as such:

1. Draw a circle

2. Draw a bigger circle around the first circle

3. Place a dot in the center of both circles

4. Extend eight lines from this center point to the outer circle, evenly

5. Draw small circles randomly throughout the inside of the smaller circle

• As a class, compare student results. Do they all look the same?  What is different? Why?

• After this discussion, present to students the expected image:

• Did anybody in the classroom draw a pepperoni pizza like the image shown? If not, then why not? What could I have done to make the instructions more clear? What parts of my instructions were unclear?

• Students will now be tasked with performing this activity on their own. Each student will draw their own image on paper (nothing too difficult) and write out the instructions on how to replicate their image. Students should NOT allow anybody else to see their original drawing. The instructions should be clearly listed (1, 2, 3, ...), legible, and use language that is appropriate.

Lesson Two:  (45 Minutes)

• After reviewing the previous lesson's materials, students will share their instructions with a peer partner. Again, the original drawing should NOT be shared - only the instructions. Each student should draw their partner's image to the best of their abilities based on reading through the instructions, sequentially. When finished, each partner returns their drawing (output) along with the original instructions (input).

• Students can now take time to analyze the drawing and see where their instructions had gaps or were unclear. Students should revise their instructions to better match their original drawing.

• When both students in the partnership are finished, they should share the revised instructions with one another. Again, each student should draw their partner's image to the best of their abilities based on reading through the revised instructions, sequentially.

• OPTIONAL: Having the students share their results is a great opportunity to incorporate ELA presentation skills and further engage in student understanding of sequence processing.

• Students should reflect on the process of instruction processing and "debugging" wherein errors in the instructions are corrected. Have students write their thoughts on what portions of their instructions were clear and which needed correction, and why.

For students who finish early, have them revise their instructions a second time. If their original design was not difficult enough, have them add elements to the drawing and instructions that will challenge their ability to describe what is being drawn.