A television reality show offers potential chefs a pile of ingredients. They all have the same ingredients, but they can cook what they like. There are more ingredients than they need, so an early decision is which ones to use and which to discard. Imagine a science, art or design and technology lesson like this. Pupils design or construct something from a range of given materials. In making those initial decisions- what to make, what to use, what not to use – they have to become very close to the capabilities of those materials and to the appropriate design and construction processes.