now i think that's better than nothing, but i think one has to take it a stage further than that and say that erm the concepts and the processes in science do build logically one upon the other, in a coherent and meaningful way, and that's important for teachers to appreciate what that meaningful sequence is and that, you know, the lucky dip idea is, as i have said, better than nothing, but it's so much inferior to the notion that teachers should be aware that there is a progression in science and that they can teach children progressively from a very early age onwards and build meaningful knowledge upon meaningful knowledge.