At the end this turned out to be the most difficult thing to do for our students. Some partner's students were old enough to design worsheets complete on their own. They were able to consider content and design. But the most of our students were not able to cope the really challenging task to get a chemical content into a worsheet for students at school. Thus the most of us were settled with the students giving classical worksheets a new look by adding their design.
Here you can download them