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Lesson 4
Events
The Foos Chapter 4
Then ask a simple question that most students will be able to answer:
What is the color of my hair?
What is the weather today?
What day of the week is it?
Introduction(cont.):
Call on a student who has a hand raised and let him/her answer the question. Then
ask the class how you knew the student wanted you to call on him/her.
The class should mention that the student raised his/her hand.
Explain that when the student raised his/her hand, it is an event because it was an
action that prompted something else to happen--you calling on the student.
Ask the class if they can think of any other types of everyday events. You might need
to clarify that you are not talking about events in the conventional sense, like a
birthday party or a sports game. In computer science, events are actions that cause
something else to happen.
Here are some examples:
- If you have a call and response to get the student’s attention, your “call” is the
event and their response is the resulting action (e.g., you clap three times and the
class claps once to let you know they are paying attention; you turn the lights off
and the class becomes quiet).
- When the alarm clock goes off (the event), you wake up (resulting action of the
event).
- When the street light turns green (the event), cars start driving (resulting action of
the event)
- When you click the power button on a computer (the event), the computer turns on
(resulting action of the event).
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