Last year I used some of the resources from PBS Design Squad with my primary 6 science and engineering club.  On the website there  is a whole section of resources aimed at parents and educators.  The resource I used was a unit called, ‘On the moon’ and we worked on a number of challenges which included creating a ‘lander’ in which the learners, working in groups, had to try out different ideas for shock absorption.  These resources are obviously not tied directly to our curriculum but are very useful for science and engineering clubs and would give some ideas for interdisciplinary challenges that could be the culmination of design technology and science departments working on curriculum knowledge and skills and could create opportunities  for application. The ideas could also easily be adapted to other contexts.   One of the things that I like about them is, that they have a prompt sheet to introduce the challenge, that gives a question or hint to help the learners think about a possible way in.