Building the LeScratch smart house

Imagine that you are still half awake on your sweet bed early in the morning. It's time to wake up but you expect something more interesting to replace the ringing of your alarm clock. What about this situation: you wake up to the singing of a gentle bird rather than the alarm clock, which might make you panic. Then, you touch a button on the wall and your favorite kind of music starts to play. Brushing your teeth, you glance at the LCD screen, showing the weather report and timetable; it gives you suggestions on what to wear and reminds you of your schedule for the day. After you get ready and head to the garage, the doors open by themselves when you get closer to them; lights in corridors turn on when there's a slight sound and switch off in intervals.

The LeScratch handler program is very simple to use and flexible when adding new extensions; apart from current realized sensor modules, it's easy to add more new modules as well. To implement all these...