Computer Science Teacher
Computer Science Teacher - Thoughts and Information from Alfred Thompson

April, 2008

  • Computer Science Teacher - Thoughts and Information from Alfred Thompson

    RoboChamps – Online, Virtual Robot Competition


    Most robotic competitions are fairly expensive to enter. The hardware is expensive, hard to assemble and tends to break at the worst possible times. They are lots of fun for hardware geeks but not as much fun for software geeks. RoboChamps is different – RoboChamps is mostly about the software!

    The idea is that there are different challenges modeled in a simulator. Participants have simulated robots to program to solve the challenge. The prizes (there have to be prizes) include actual physical robots. From the RoboChamps home page:

    RoboChamps consist of a series of challenges. Each challenge comes with a 3-D simulation environment, a robot, a challenge scenario, and the rules for completing the scenario. From there, it’s up to your creativity and coding skills. Using .NET, code your robot to complete the challenge successfully, and submit an entry to the RoboChamps League. A referee service will be running to make sure the rules are being followed, determine your score and send it back to

    Max interviews one of the people behind RoboChamps on Channel 8. It sounds like a lot of fun. One of the things they demo is how one will be able to watch robot runs in the simulator and see things from different angles and locations.

    The official rules limit competitors to people 18 and over so it might be something interesting for HS seniors to try as they finish up the school year. But I think it would be interesting for others to try as a place to show of their skills. The software is all free anyway!

  • Computer Science Teacher - Thoughts and Information from Alfred Thompson

    Popfly Coin Flip Mashup Tutorial


    This is a tutorial I put together to provide a hands on experience for some teachers I am doing a workshop for today. I did a copy from a Word document and paste into Windows Live Writer to see how it works as a blog post. Sorry about all the images if you are on a slow connection. I don't usually include much in the way of images.

    Open Popfly –

    Sign in

    Select Mashup from the Create Stuff menu


    Drag a Timer, Calculator, LessGreaterCompareClass, and SimpleImages blocks

    Timer under Tools

    Calculator under Tools

    LessGreaterCompareClasss under Everything else

    SimpleImages under Display

    (Hint – use the search feature as a shortcut)

    You should have something like this:


    Connect the blocks with arrows by clicking first on a blue dot on the right of the input/sending block and then on the changing color dot on the left of the receiving block.


    Note: The ! signs indicate that commands must be specified for those blocks.

    clip_image010Set the Timer

    Click on the wrench symbol to expand the block

    1. Enter 0.5 for the Frequency

    2. Enter 50 for the number of ticks

    3. Click the wrench to return to normal

    Set the Calculator to return a RandomWholeNumber with a maximum value of 2


    Set the LessThenCompareClass block to Return coin images


    1. Set the source for Item 1 to Calculator and the Value to [output integer] which is the default

    2. Set the value for item2 to 1 so that the random number will be compared to see if it is equal to, less than, or greater than 1

    3. Select a coin to flip from the list below and place one URL for equal and less results and the second image URL for resultIfGreater (Note: Images are from the US Mint for educational uses) (penny front) (penny back) (nickel front) (nickel back) (dime front) (dime back) (quarter front) (quarter back)

    Set SimpleImages to get an imageURL from LessGreatorCompareClass


    Select Preview clip_image018 to run your mashup

    Done with pennies it should look something like this:


    Select Customize to return to editing your mashup


    Select Show Console to get a close look at what is going on behind the scenes


    Use the Save As option at the top of the screen to save your mashup


    On your own:

    1. Use the User Input block to let the user select the number of times to flip coins

    2. Use the SimpleLight block to get randomly placed coins

    Note: The original version of this mashup was by Mark Frydenberg of Bentley College

  • Computer Science Teacher - Thoughts and Information from Alfred Thompson

    XNA Links for Teachers (and other learners)


    I’ve been hearing from a lot of high school computer science teachers that they are looking for some fun and educational things to do with their AP CS students once the exam is over. For some of these teachers some XNA looks promising. For those people and more I decided to put this collection of resources together in one place. I’m open to adding more if people leave me comments or send me email. What works for you to get jump started with XNA and game development?

    Official XNA Sites


    Projects – By and For Educators

    Very Silly Games

    Very Silly Games is a "Library of Gameplay silliness" from which you can pull down fully working XNA games you can play instantly on your computer or, once you have joined the XNA Creators Club, on your Xbox 360.

    XNA Game-Themed Assignments

    Kelvin Sung from the University of Washington at Bothell has a project that is building XNA Game-Themed assignments for use in computer science classes.

    The project home page is here.

    The Release Guide with a lot of information and links is here.

    Video Demos


    GuitarMatey is a 3D game for the Xbox that allows you to improvise guitar music with the accompaniment of a backing track. Five pirates dance for you as you play the game. While GuitarMatey lacks a real objective or purpose, it is perfect to help you learn about developing 3D games for free using XNA and our partner tools. 

    Full details and links to the videos may be found here.

    When Cods Collide

    Betsy Aoki has created a simple 2D game in XNA that involves collision detection. It looks like a useful series and it is a fun read. So here are the links:

    · Making a 2D XNA Game - When Cods Collide - Part 1

    · Making a 2D XNA Game - When Cods Collide - Part 2

    · Making a 2D XNA Game - When Cods Collide - The Final Chapter

    Modify an existing game in 10 minutes

    Hilary Pike has created a short quick moving demo/screen cast on modifying an existing 2-dimensional XNA based video game. In just 10 minutes she walks the viewer through some key gaming concepts and then adds Collision Detection and Score Keeping to the game.

    XNA Pong Game

    Dan Waters has created a Pong game as a tutorial for beginners. This might be a piece of code a bright student might enjoy improving on themselves.

    Other Sets of Links From Teachers

    Brian Scarbeau’s XNA Class links -

    Patrick Coxall’s collection of videos -

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