I won’t quite say that it’s by popular demand – but after a comment I made on the TES Forums about a problem-solving activity I did back in the mists of time, a few people expressed interest. I couldn’t find the original information so I’ve had to reproduce it from memory. The downside is that there isn’t as much detail as there was in the Homeopathy scheme I put here a few weeks back. But hopefully it will be useful and/or interesting.
The basic idea is that students attempt several different activities, all based around the idea of surviving and eventually escaping from a desert island. They have to use various aspects of KS3 science to do so, as well as some creativity and a fair bit of ingenuity. There will be sellotape, or for those more experienced, duct tape. (Basic survival necessity).
What it doesn’t have is the complete set of printable resources I did for the homeopathy scheme. Partly this is because how you use the resources will depend on time and equipment available. Partly it’s because I just haven’t had time to recreate it all. Please feel free to send (or link to in the comments) anything you have that could or should be added.
Printable: survival science as pdf
Teaching Science 
I just saw this and love your idea thanks for sharing it and I might have a go at a few soon!