Lesson 11: Events Unplugged: The Big Event

Unplugged | Event

Overview

Events are a great way to add variety to a pre-written algorithm. Sometimes you want your program to be able to respond to the user exactly when the user wants it to. That is what events are for.

Purpose

Today, students will learn to distinguish events from actions. The students will see activities interrupted by having a "button" pressed on a paper remote. When seeing this event, the class will react with a unique action. Events are widely used in programming and should be easily recognizable after this lesson.

Agenda

Warm Up (15 min)

Main Activity (15 min)

Wrap Up (15 min)

Assessment (10 min)

Extended Learning

Objectives

Students will be able to:

  • Recognize actions of the teacher as signals to initiate commands.
  • Practice differentiating pre-defined actions and event-driven ones.

Preparation

Links

For the Teacher

Vocabulary

  • Event - An action that causes something to happen.

Support

Report a Bug

Teaching Guide

Warm Up (15 min)

Vocabulary

This lesson has one new and important vocabulary word:

  • Event - Say it with me: E-vent

An action that causes something to happen.

A Series of Events

  • Prep your class to answer a question:
    • "I'm going to ask you a question. I want you to raise your hand if you want me to call on you for the answer."
    • Ask a simple question that most of your students should be able to answer, such as:
      • How many thumbs do I have?
      • What is bigger, a bird or a horse?
    • Call on a student who has their hand raised and let them give their answer.
    • Upon finishing that display, ask the class how you knew that the student wanted you to call on them.
      • Your class will likely mention the raising of the hand.
    • Explain to everyone that when students raise their hand, it is an "event" that causes you to know that they want to be called on.
  • Ask the class if they can think of any other events that give signals.
    • You may need to remind them that you're not talking about an event like a birthday party or a field trip.
    • If they have trouble, you can remind them that an event is an action that causes something to happen.
      • What about an alarm clock going off? What does that make happen?
      • What about pressing "Start" on the microwave? What does that do?
      • What about pressing the power button on your tv remote?
  • Today, we're going to create programs with events.

Main Activity (15 min)

The Big Event

Lesson Tip

If your students seem confused, talk about their favorite games and all of the ways that they let the characters know what they're supposed to do. Point out how the game would be really boring if it ran from start to finish without any events required.

  • Do you remember helping the Flurbs find fruit?
    • In that exercise, you knew in advance exactly where you wanted your Flurb to end up, so you could make a program that took them from start to finish without any interruptions.
    • In most real programs, we can't do that because we want to have options, depending on what the user needs.
      • Say that I only want my character to move when my finger is on the screen of my phone. I would need to program the character to only move when I put my finger on the screen of my phone.
      • Putting my finger on the screen would then become an "event" that tells my character to move.

In earlier lessons, we created algorithms that allowed us to control a friend or Flurb for several steps at a time. It was fun and useful, but what happens when you don’t know everything that you want your friend to do in advance? This is where events come in!

Directions:

  • Project the Event Controller onto your classroom screen.

  • Decide with your class what each button does. We suggest:
    • Pink Button -> Say “Wooooo!”
    • Teal Button -> “Yeah!”
    • Purple Dial -> “Boom!”
  • Practice tapping the buttons on the overhead and having your class react.
  • Add some button sequences into the mix and have the students try to keep up with their sounds.
  • Let your class know that every time you push a button, it is an “event” that lets them know what they are expected to do next.
  • Get the class started on a planned task before interrupting them again with the buttons. We suggest:
    • Counting to 10
    • Singing “Old MacDonald”
  • Once their plan is underway, interject button presses sporadically.
  • Continue the blend until they understand the difference between actions that are guided by a plan and those that are event driven.

Wrap Up (15 min)

Flash Chat: What did we learn?

  • Why do we need to be able to handle events in a program?
  • What are some other kinds of events that you can think of?

Journaling

Journal Prompts:

  • What was today’s lesson about?
  • How did you feel during today’s lesson?
  • Draw an event that caused an action today.
  • Draw an action that was caused by an event that happened today.

Assessment (10 min)

CSF The Big Event Activity - Assessment

  • Hand out the assessment activity and allow students to complete the activity independently after the instructions have been well explained.
  • This should feel familiar, thanks to the previous activities.

Extended Learning

Use these activities to enhance student learning. They can be used as outside of class activities or other enrichment.

One Person's Event is Another One's Reaction

Assign each student an event to watch out for, and an appropriate reaction to that event. Chain the actions so that each child's reaction becomes an event that triggers the reaction of another student. Keep assigning until everyone has something to do and everyone makes someone react.

Eventopalooza

Break the class up into groups. Using the Events Controller, assign each group a different reaction to the same button. Do this for all three buttons, then watch the chaos!

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Student Instructions

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Student Instructions

Standards Alignment

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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-11 - Debug (identify and fix) errors in an algorithm or program that includes sequences and simple loops.