3.4 Reactions
Students are introduced to "If-Else" command in a fun reaction game. When the mouse pointer touches a sprite, the sprite reacts!
Sprite reactions range from changing color to speech. Students continually test if mouse pointer is touching sprite, when condition is True, a reaction happens!
OBJECTIVES:
OBJECTIVES: By the end of this lesson, students will:
identify an If-Else conditional statement
understand how a script branches through If-Else statement, choosing one path or another.
recognize reasons to continually test a condition.
TEACHER RESOURCES:
Standards
CSTA 2-AP-12: Design and iteratively develop programs that combine control structures, including nested loops and compound conditionals.
DO NOW:
Do Now Digital Citizenship (5 minutes)
Watch Copyright and Fair Use (2:45)
Discuss:
What is copyright law?
How can you use something from the internet that has a copyright?
How is fair use different from copyright law?
Teacher Guidance
Copyright law protects your control over the creative work you make, requiring people to get your permission before they copy, rework, or share your work.
You can use something with a copyright if you check who owns it, get their permission to use it, give credit to the creator, buy it if necessary, and use it responsibly.
Fair use is using someone’s work without permission as long as it is for schoolwork & education, news reporting, criticizing or commenting, and comedy or parody. Under fair use, you can only use a small piece of the work, you must add new meaning to it, you must rework it and use it in a totally different way, and you cannot make money off your creation.
Mini-Lesson (5-10 minutes)
Mini-Lesson (3-5 minutes)
Branching:
The concept of branching code is fundamental to programming. If an event happens, do one thing. If a different event happens do another thing.
In today's lesson, the students will use an If-Else statement.
eg. IF it is snowing THEN wear boots ELSE wear shoes.
The ELSE portion makes sure that a different action is performed. Without the ELSE action, your students might be barefoot!
Code can branch down different paths:
If a condition is True,
one set of commands are processed.
If condition is Not True,
a different set of commands are processed
Project (20-30 minutes)
Today's project is fun. The student page should be sufficient to let students work at their own pace. Students should be creative, focus on their sprites reactions and use the If-Else in a meaningful context. Students should share and showcase their work with others.
This lesson is more about exposure to the If-Else concept than about mastery.
If-Else is a difficult for 11-13 year olds to conceptualize. That is OK. This project can be modified to work with the simple IF statement first, before trying the IF-ELSE.
TEACHER GUIDANCE: Handout is two pages: first page is helper for project; second page is helper for the concept of Branching.
Students may ask what is the difference is between these commands:
With "When this sprite Clicked: pointer needs to click on the sprite.
With if < touching >, pointer touches ( passes over )the sprite, there is no need to click.
Close-Out (5 minutes)
Close-Out (5 minutes)
Discuss the following questions:
Give me an example of an IF-ELSE statement. eg. "IF it rains, I take an umbrella, ELSE I take my sunglasses."
What is the "condition" that is being tested? (Raining?)
Draw the example condition tree as a flowchart on the white board. Ask class to follow along with flow of the script.
If TRUE, what will happen? If False, what will happen?
Below is an example of the flowchart that the teacher would draw on the whiteboard using the students example condition.
Note: In a flowchart, conditions (eg raining?) are always in diamonds and commands (eg. take sunglasses) are always in rectangles.
If TRUE, what will happen? If False, what will happen?
Potential Responses
If True, take the umbrella.
If False, take the sunglasses