May 5, 2010

Programming for kids

Filed under: Devnology,Learning,Programming — Freek Leemhuis @ 4:44 pm

Some time ago I was running out of time for the Devnology codefest assignment to create my own Tetris clone. At the same time I was trying to spend some more time with my daughter, who is 8 years old now. She is sometimes very bored from school, which I sympathise with – I was the same at that age I guess. So I thought this would be a good time to try and see if she would be interested in programming. After some research on visual programming languages for kids I to give Scratch a go to see if we could build something together.
It took us very little time to get going, and in no time we had some of the build-in characters moving across the screen. Visual programming makes it relatively easy to grock some of the core concepts of programming. Loops, conditions, variables – you just drag them on a pane and they snap together.

We started out by discovering animation, and this is when something amazing happened. We added some animation logic while the app was running, and it changed its behavior while it was running.
I had a flashback to Alan Kay’s demo on TED – a powerful idea about ideas. If you’ve not seen it, go ahead and watch – it will be 20 minutes well spent.

Reading up on Scratch I found it is actually build on Squeak, an implementation of the Smalltalk language and environment.
After some goofing around we set off to create a simple tetris clone. Except tetris isn’t that simple, and with no means of testing or debugging, one quickly realises this is really an educational tool but not so good in producing something more complicated.
We did get sort of half-way, but it’s fair to say that by then neither of us was enjoying the experience very much.
I’m very impressed with Scratch as a tool for education young children, and it’s a real joy to see the thoughts and discoveries of your child click into place going through some of the basics. Some advice for other fathers: take it slow, one step at a time. After an hour or so trying to explain everyting, it turned out to be a lot to ask for from Hannah. ‘Can I play with my playmobile now daddy?’ Ofcourse you can, just wait while your daddy finishes this real simple tetris game…


October 15, 2009

On the nature of community driven events

Filed under: Community,Devnology,Events,Learning,Speaking — Freek Leemhuis @ 5:45 pm


lowscore Last week I was involved in organizing a Scala workshop, and from the feedback we received it was notable that some of the issues that were mentioned were more to do with the expectation of participants than with the actual content.The average rating from the evaluation for this event was 7.3 (on a scale from 1 to 10), and while that might seem decent it is dramatically lower then scores for our previous events.Some of the feedback that was provided was very fair. For example, it was mentioned that the tempo could have been higher, and it could have. The typical participants of Devnology meetings have way more smarts and passion about them than any other group I have participated in, so we need to become better at tailoring our meetings accordingly.

Another point of criticism we received was that the facilitators did not seem to know all the ins and outs of the subject matter. This in my opinion is a result of the position we take in organizing these types of events: there should not be one expert explaining to the rest everything there is to know, but rather a situation where there’s enough preparation done to go through the material, and in the process learn from each other.

Under these conditions, chances are a lot bigger that it will be an interactive event, with active participation.

This way, you get to know the attendees, learn what knowledge and experience they can contribute, possibly even beyond the event itself. The meetings will become more lively and interesting, and more in line with the ideas behind the Unconference.

Having an expert capable of explaining everything on a particular subject may not improve the experience, expecially if you lose a level of interaction. We will therefore continue to encourage members of the community to take on a subject and create a learning events that is geared toward learning together.

Obviously, this will only be a success if the more knowledgeable participants are aware of this and willing to share their skills and ideas. If you are aware of points being missed or if you have information or skills that can contribute, one way to react it to sit back and be bored. It might however be better to ask yourself this question: what have I done to improve the experience of this event for some (or all) of the other participants?

Let me paraphrase what this guy said:

Ask not what your community can do for you, ask what you can do for your community!

I don’t mean to sound obnoxious here and I certainly don’t want to put people off from attending. What I hope to achieve with this post is to make our viewpoints regarding these issues clear and hopefully prevent misunderstanding in the future.



Please feel free to respond!

April 2, 2009

Code Fest 01

Filed under: Community,Devnology — Freek Leemhuis @ 4:00 pm

Some night that was! I was well impressed with the people that showed up, discussion and banter flowed between them based on a shared passion for technology and interest in other people’s approaches.


On this first Code Fest (all in Dutch, apologies) we had implementations of that old classic, James Conway’s Game of Life. On the night we had demonstrations of implementations in Flex, Erlang, Haskell, C++, Alloy, Java, CosMos and the Google App Engine. It certainly had my head spinning, and with what I thought was a cracking atmosphere we couldn’t have asked for more. We have invested a lot of time and energy in getting this thing of the ground, but yesterday evening alone was worth every bit of it.

Thanks all for a great evening.

On a sidenote, I was playing with this domain model to describe Devnology, and thought I’d share it here:



Geek as I am, it helps me focus and explain what I think we can achieve : Building a technology agnostic community by organising events that have high interaction between passionate developers. Enable interaction between academia and the software development industrie (software craftsmen, if you like).

With result like yesterday and the software testing event at TU Delft things are shaping up. Come and join us at our next meeting!

February 20, 2009


Filed under: Community,Devnology — Freek Leemhuis @ 9:24 am

The cat is out of the bag! It’s been a long time in the making, but finally…. coming to a theatre near you very soon… It’s…..devnology

Our first event is planned for the 1st of april (no joke, I promise) and is now open for registration. Do come!

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