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Lesson 29: Variables with Artist

Overview

In this lesson, students will explore the creation of repetitive designs using variables in the Artist environment. Students will learn how variables can be used to make code easier to write and easier to read, even when the values don't change at runtime.

Purpose

This stage teaches the most basic use for variables, as a constant that reoccurs frequently in a program.

Agenda

Warm Up (15 min)

Bridging Activity - Variables (15 min)

Main Activity (30 min)

Wrap Up (15 min)

View on Code Studio

Objectives

Students will be able to:

  • Assign values to existing variables.
  • Utilize variables in place of repetitive values inside of a program.

Preparation

Links

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

For the Teachers

For the Students

Vocabulary

  • Constant - A variable used throughout a program that never changes value
  • Variable - A label for a piece of information used in a program.

Support

Report a Bug

Teaching Guide

Warm Up (15 min)

Introduction

This is the first online lesson dealing with variables, so it might be a worthwhile exercise to review the "Envelope Variables" unplugged activity from last time, as well as the vocabulary that was introduced in that lesson.

Discussion:

  • What is a variable? (A placeholder for a piece of information that can change.)
  • When can a variable be helpful? (When you don't know what information is going to be used in a certain place until runtime, or when you have lots of places that one piece of information will be used, but that information might change someday.)

Ask the class when they could see a variable being helpful in programming. When would they NOT want to use a variable?

If the class seems interested, continue the discussion. Otherwise, move on to one of the bridging activities.

Bridging Activity - Variables (15 min)

This activity will help bring the unplugged concepts from "Envelope Variables" into the online world that the students are moving into.

Unplugged Activity Using Variables as Constant

Discuss: Remember our robot article? It used each variable only once...but what if I wanted to mention the robot's name several times?

Display: Write a paragraph on the board that refers back to the name of a specific robot several times. Ask the students what happens when you need to make the article about a different robot.

Think/Pair: Ask students to work together to see if they can come up with an idea to make changing the article for each robot easier.

Share: Work with students until you eventually get to the place where you have defined a variable called robotName somewhere before the paragraph, then set robotName equal to the robot that you are writing the article about. Replace all specific naming instances for the previous robot with the variable robotName.

Preview of Online Puzzles as a Class

Demo: Display a puzzle for the class. We recommend the 6th puzzle. Go over the code with the students to make sure they understand what's happening before they help you convert the code to use variables. Can they think of something that might happen that would make them really glad that they used variables instead of hardcoded numbers?

Transition: Now it's time for your students to move to their own machines and get started!

Main Activity (30 min)

CSF Express Course 2018 - Website

Notice that this stage first covers the idea of a variable as a constant (a variable that you use in many places, but it does not change.) This might be something that students find helpful as they're creating their own projects.

Watch out for puzzle #6. It is the first time that students will be expected to set a variable on their own. This can be tricky if they don't have a true grasp on the concept. If they're having trouble, send them back to the prediction level (#5) and have them explain to their partners why the answer ended up what it was. Once both partners are convinced, let them continue back to puzzle #6.

Wrap Up (15 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?
  • What is a variable? Why is it helpful in programming?
  • How well do you think you understand variables? (Answer on a scale from 1-5 or with an emoticon.) If you're having troubles, can you put into words what you don't understand?

Standards Alignment

View full course alignment

CSTA K-12 Computer Science Standards (2017)

AP - Algorithms & Programming
  • 1B-AP-09 - Create programs that use variables to store and modify data.
  • 1B-AP-11 - Decompose (break down) problems into smaller, manageable subproblems to facilitate the program development process.

Cross-curricular Opportunities

This list represents opportunities in this lesson to support standards in other content areas.

Common Core English Language Arts Standards

L - Language
  • 5.L.6 - Acquire and use accurately grade-appropriate general academic and domain-specific words and phrases, including those that signal contrast, addition, and other logical relationships (e.g., however, although, nevertheless, similarly, moreover, in addition).
SL - Speaking & Listening
  • 5.SL.1 - Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 5 topics and texts, building on others’ ideas and expressing their own clearly.
  • 5.SL.1.a - Come to discussions prepared, having read or studied required material; explicitly draw on that preparation and other information known about the topic to explore ideas under discussion.
  • 5.SL.4 - Report on a topic or text or present an opinion, sequencing ideas logically and using appropriate facts and relevant, descriptive details to support main ideas or themes; speak clearly at an understandable pace.
  • 5.SL.6 - Adapt speech to a variety of contexts and tasks, using formal English when appropriate to task and situation.

Common Core Math Standards

G - Geometry
  • 5.G.2 - Represent real world and mathematical problems by graphing points in the first quadrant of the coordinate plane, and interpret coordinate values of points in the context of the situation.
  • 5.G.3 - Understand that attributes belonging to a category of two- dimensional figures also belong to all subcategories of that category. For example, all rectangles have four right angles and squares are rectangles, so all squares have four right angles.
MP - Math Practices
  • MP.1 - Make sense of problems and persevere in solving them
  • MP.2 - Reason abstractly and quantitatively
  • MP.6 - Attend to precision
  • MP.7 - Look for and make use of structure
  • MP.8 - Look for and express regularity in repeated reasoning
NBT - Number And Operations In Base Ten
  • 5.NBT.5 - Fluently multiply multi-digit whole numbers using the standard algorithm.

Next Generation Science Standards

ETS - Engineering in the Sciences
ETS1 - Engineering Design
  • 3-5-ETS1-1 - Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost.