Transcript Professor Dan Grossman`s Squeak Presentation

Visual Programming Via
The Squeak Car Demo
Dan Grossman
University of Washington
CS4HS
August 6-8, 2009
This 120 minutes
• 20 minutes:
– introduction
– “cooking-show demo”
• 50 minutes: paired up in the lab “trying it out”
• 50 minutes:
– recap concepts
– a demo I made in 10 minutes
– brainstorm
2
“Visual programming”
• “Virtual worlds” for scripting, simulation, animation,
building control systems, etc.
– “Discovering” core math, science, and computer
science with some “computer game” feel
• Popular ones with amazing stuff:
– Squeak Etoys, Scratch, Alice
• Today: A demo for 11-year-olds
– The point is the idea & approach
– Not the specific content
• (make up own or search web later)
3
Why?
• Virtual scriptable worlds compared to real-world
– Easier to control
– Faster
– Cheaper
– As a result: More fun
• Computational concepts without a CS class
– Scripting
– Modeling
– Simulation
– Feedback and control loops
– Conditionals
– (plus tons of useful math, probability, statistics, …)
4
Why me?
• Computer science faculty since 2003
– Programming languages
(ways to think about computation)
– Believe “computational thinking” is essential for all
college-prep high-school students
• Not the same as programming class
• I never programmed until college
– But I’m not a high-school teacher
• Show you Squeak; hope you think it’s useful
5
Cooking-show
• 4x-speed version of what you’ll do in the lab
– Feel free to play around also, but try to get through
most of this
– Step-by-step instructions in lab, so just “get a
sense” here
• By the way, I’m new to Squeak – you pick it up fast
6
Outline
1.
2.
3.
4.
5.
6.
7.
8.
Paint a car; keep it
Use mouse and object viewer to move car
Skip saving/loading projects
Script circles/polygons (pen down)
Steering wheel connected to car
“Robot” car that follows the road
Car with random speed
(Time permitting, car that accelerates at each step)
7
Let’s go try it ourselves!!!
8
This 120 minutes
• 20 minutes:
– introduction
– “cooking-show demo”
• 50 minutes: paired up in the lab “trying it out”
• 50 minutes:
– recap concepts
– a demo I made in 10 minutes
– brainstorm
9
Outline
1.
2.
3.
4.
5.
6.
7.
8.
Paint a car; keep it
Use mouse and object viewer to move car
Skip saving/loading projects
Script circles/polygons (pen down)
Steering wheel connected to car
“Robot” car that follows the road
Car with random speed
(Time permitting, car that accelerates, at each step)
10
A ton of CS in there
• Using mouse and object viewer to move car
– State of a model
– Multiple representations for viewing and
controlling the model
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A ton of CS in there
• Script circles/polygons
– Expressing repetitive tasks via an algorithm
– Automating repetitive tasks
– Approximations, derivatives, limits
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A ton of CS in there
• Steering wheel
– “Wires” for connecting outputs to inputs
– Perspective and relative positions
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A ton of CS in there
• Smart car
– Feedback and control systems
– Conditionals
14
A ton of CS in there
• Random speed
– Simulation of a random process for collecting
statistics
• A key alternative to mathematical analysis
• So much faster than rolling real-world dice
• Let me show you my “roulette car”…
– In theory, analysis is more convincing
– In practice, many people learn visually
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Why?
• Virtual scriptable worlds compared to real-world
– Easier to control
– Faster
– Cheaper
– More fun
• Computational concepts without a CS class
– Scripting
– Modeling
– Simulation
– Feedback
– Conditionals
– (plus tons of useful math, probability, statistics, …)
16
Much, much more available
• Plenty of online information, forums, etc.
• Squeak Etoys school projects:
– http://squeakland.org (not squeak.org)
– Slightly newer version than we had in the lab
– Try Showcase, then Showcase by Age
• Actually, instead try out:
– Scratch: http://scratch.mit.edu/
– Alice: http://www.alice.org/
– (what? and start over after 2 hours?? )
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So…
What in your courses could use something like this?
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