# Lesson 10: Loops in Artist

## Overview

Returning to loops, students learn to draw images by looping simple sequences of instructions. In the previous plugged lesson, loops were used to traverse a maze and collect treasure. Here, loops are creating patterns. At the end of this stage, students will be given the opportunity to create their own images using loops.

## Purpose

This lesson gives a different perspective on how loops can create things in programming. Students can also reflect on the inefficiency of programming without loops here because of how many blocks the program would require without the help of `repeat` loops.

## Objectives

### Students will be able to:

• Count the number of times an action should be repeated and represent it as a loop.
• Decompose a shape into its largest repeatable sequence.
• Create a program that draws complex shapes by repeating simple sequences.

## Preparation

Heads Up! Please make a copy of any documents you plan to share with students.

## Vocabulary

• Loop - The action of doing something over and over again.
• Repeat - Do something again

# Teaching Guide

## Warm Up (10 min)

### Introduction

• Quickly review the definition of a loop, the action of doing something over and over again.
• Discuss different patterns like zigzags and stairsteps.
• How would you explain to someone how to draw that pattern?
• How could you draw this using a loop?

In the artist levels students will be using 45 degree angles described as northwest, northeast, southwest, southeast. We recommend briefly discussing these directions with the class and drawing an image for students to refer back to.

## Main Activity (30 min)

#### Teacher Demonstration

Teacher Tip

Remind the students to only share their work with their close friends or family. For more information watch or show the class Resource not found.

We've included some multiple choice prediction levels that are difficult for non-readers. These levels are optional for you to review with your class to help prepare for the puzzles to come. Alternatively, these could be used after finishing the stage as a review for the class.

Prediction Levels:

## Wrap Up (5 - 10 min)

### Journaling

Having students write about what they learned, why it’s useful, and how they feel about it can help solidify any knowledge they obtained today and build a review sheet for them to look to in the future.

#### Journal Prompts:

• What was today’s lesson about?
• How did you feel during today’s lesson?
• Draw some stairs. Imagine the loop needed to draw this.
• Draw something else in your life that uses loops.

## Standards Alignment

#### CSTA K-12 Computer Science Standards

AP - Algorithms & Programming
• 1A-AP-09 - Model the way programs store and manipulate data by using numbers or other symbols to represent information.
• 1A-AP-10 - Develop programs with sequences and simple loops, to express ideas or address a problem.
• 1A-AP-11 - Decompose (break down) the steps needed to solve a problem into a precise sequence of instructions.
• 1A-AP-14 - Debug (identify and fix) errors in an algorithm or program that includes sequences and simple loops.