Monday, August 31, 2009

40 maths shapes challenges

Forty shapes to make in Scratch or some other version of logo, such as Turtle Art. It's hard to see the thumbnail but click on it for a larger view.

This is one of the best sheets ever for teaching maths (designed by Barry Newell):
  • the logo turtle or scratch cat acts as a transitional object between the concrete maths shape and the abstraction of the script that makes the shape
  • the sheet includes both simple and complex shapes, increasing in order of complexity, there is a challenge there for everyone
  • many of the more complex shapes are made up of combinations of the simpler shapes

Source: Barry Newell's Turtle Confusion (1988)

Saturday, August 29, 2009

scratch challenges update

I'm using this challenge sheet with Year 10s at the moment and have updated it, improving the order of challenges and adding some extensions. The first one is very popular with students. Scratch is a free download.

btw there is a new scratch page for educators, scratched, but I haven't checked it out fully yet.


1) Use the Letter shapes to write your first name on the page. Then introduce some special effects such as making the letters wobble and change their appearance.

2) Point, click and move
Make an object both point and glide towards the mouse position when you click on the stage
Hint: Motion > point towards
Hint: Sensing > mouse down?

3) Make Dan or Anjuli or Cassy or ballerina dance to a beat, using all of their dance shapes

4a) Make two animals have a forwards and backwards conversation
Hint: Use broadcast
4b) Make it an interesting conversation with each animal speaking at least 3 times and making gestures too

5) Make 2 different balls move around on the stage
a) the first ball moves in straight lines but bounces randomly whenever it hits the edge
b) the second moves randomly, changing direction all the time

6a) One sprite chases another sprite around the stage. The first sprite moves in straight line but bounces off the edge randomly. The chasing sprite chases the first sprite but is moving slower.
b) Extension – if the chasing sprite catches the other sprite then it says something sensible and makes a suitable sound

7a) Play all the different drum sounds automatically
Hint: create a variable for the drum number
b) Extension – keep recycling through all the drum sounds automatically

8) Make a sprite gradually grow in size and then shrink
Hint: make a size variable

9a) Count down on a timer. A rocket takes off when you reach zero
Hint: Use the number icons in the letters folder
9b) Your rocket has pulsating exhaust and disappears at the top of the screen

10) Add, multiply or subtract two variable numbers
Hint: Just to do addition only you will need 4 variables: firstNum, secondNum, answer (computer calculated) and myAnswer (human calculated)

11) Variable coloured squares
a) Write a script that can draw a square of any size
Hint: Make a variable for the side length
b) Use the variable square script to draw a series of square with variable sides, with a single click
c) Now add variable pen colour and pen shade to the variable square script and use it to draw a variety of different coloured squares, with a single click

Wednesday, August 26, 2009

windows 7 sins

Correction (28th August):
I have to withdraw my support from this FSF campaign owing to their attack on the xo in the education link of their site (click on the Learn More link at their site). They conclude:
... it is expected that the main effect of the OLPC project -- if it succeeds -- will be to turn millions of children into Microsoft dependents. That is a negative effect, to the point where the world would be better off if the OLPC project had never existed.
I think this is far too over zealous and purist. Also note that at this time not a single xo has shipped with Windows.

Update (2nd September): The section I was complaining about above has been removed and replaced with:
Microsoft is now targeting governments who are purchasing XOs, in an attempt to get them to replace the free software with Windows. It remains to be seen to what degree Microsoft will succeed. But with all of this pressure, Microsoft has harmed a project that has distributed more than 1 million laptops running free software, and has taken aim at the low-cost platform as a way to make poor children around the world dependent on its products. The OLPC threatens to become another example of the way Microsoft convinces governments around the world that an education involving computers must be synonymous with an education using Windows. In order to prevent this, it is vital that we work to raise global awareness of the harm Microsoft's involvement does to our children's education.
I did write a letter to Peter Brown of the FSF on the 29th August complaining about that section but so far have not received a reply.

Just for the record my original post is below (not altered apart from this correction):

As far as I can see the following indictment of Microsoft from the Free Software Foundation is entirely correct:
1. Poisoning education: Today, most children whose education involves computers are being taught to use one company's product: Microsoft's. Microsoft spends large sums on lobbyists and marketing to corrupt educational departments. An education using the power of computers should be a means to freedom and empowerment, not an avenue for one corporation to instill its monopoly.

2. Invading privacy: Microsoft uses software with backward names like Windows Genuine Advantage to inspect the contents of users' hard drives. The licensing agreement users are required to accept before using Windows warns that Microsoft claims the right to do this without warning.

3. Monopoly behavior: Nearly every computer purchased has Windows pre-installed -- but not by choice. Microsoft dictates requirements to hardware vendors, who will not offer PCs without Windows installed on them, despite many people asking for them. Even computers available with other operating systems like GNU/Linux pre-installed often had Windows on them first.

4. Lock-in: Microsoft regularly attempts to force updates on its users, by removing support for older versions of Windows and Office, and by inflating hardware requirements. For many people, this means having to throw away working computers just because they don't meet the unnecessary requirements for the new Windows versions.

5. Abusing standards: Microsoft has attempted to block free standardization of document formats, because standards like OpenDocument Format would threaten the control they have now over users via proprietary Word formats. They have engaged in underhanded behavior, including bribing officials, in an attempt to stop such efforts.

6. Enforcing Digital Restrictions Management (DRM): With Windows Media Player, Microsoft works in collusion with the big media companies to build restrictions on copying and playing media into their operating system. For example, at the request of NBC, Microsoft was able to prevent Windows users from recording television shows that they have the legal right to record.

7. Threatening user security: Windows has a long history of security vulnerabilities, enabling the spread of viruses and allowing remote users to take over people's computers for use in spam-sending botnets. Because the software is secret, all users are dependent on Microsoft to fix these problems -- but Microsoft has its own security interests at heart, not those of its users.

Monday, August 24, 2009

the vision is more important than the mouse

During the boom at the dawn of the 21st century, bits and pieces of his framework emerged in interesting and unintended ways. Blogs, wikis, hypermedia, and networked communities of practice using dynamic knowledge repositories, such as the Center for Disease Control website, the Human Genome project, and Wikipedia proliferated. But the haphazard, market-driven diffusion of technology lacks Engelbart's foundational philosophical framework for augmenting human intellect for solving complex problems. These writings by Engelbart and his colleagues place his well-known technology achievements in the context of his grand vision for a paradigm shift in our thinking. We believe that Engelbart s philosophy is at least as significant as his inventions
The Engelbart Hypothesis: dialogs with Douglas Engelbart by Valerie Landau (Author) and Eileen Clegg (Author, Illustrator)

Much of this book also seems to be available online at the engelbartbookdialogues blog

Very smart people like Doug Engelbart ("a man who has always had ideas before words caught up to him") need popularisers

Related: kay-and-van-dam-discuss-engelbarts-ideas

Wednesday, August 12, 2009

Aurukun realities

The Politics of Suffering: Indigenous Australia and the End of the Liberal Consensus by Peter Sutton

In the video of the book launch (at Readings in Melbourne in July 2009) Marcia Langton and Peter Sutton embark on the difficult task of exposing the disastrous situation in Aurukun by spelling out difficult to face realities and contrasting that with the romantic stereotype.

Below is a 4 minute extract from the longer video here. The format is an interview /discussion between Marcia Langton and Peter Sutton. Definitely worth watching the longer version.

Background information about Peter Sutton's extensive research into the Wik people here

Book review: Untruth by Omission