For the past couple of weeks we have been hacking sugar
I introduced them to linux as a free and open system which could be modified and that we were going to do that. I taught the students some linux command line instructions (cd pwd ls cp) and how to use them. These lessons did involve quite a lot of detailed instructions. I prepared and printed word docs beforehand to make things easier.
In one lesson we changed the desktop xo icon to look like the camera icon.
In another lesson we expanded the range of layout views for the home screen to include triangle, square and sunflower.
These tutorial are already online at the floss manuals (modifying sugar) so there is no need to repeat them here
The main problem students had was using the vi editor. A few students did wreck the favoritesview.py file and sugar wouldn't reboot. I had to reflash their USB sticks.
The next step in this process is for students to make their own SVG icon and replace the xo icon with that.