Just for fun I thought I would show you some of the stuff I do on a daily basis as a teacher.
These are some MP3 Docking stations that I have made - they have a simple Amplifier electronic circuit that outputs a couple of watts per 8ohm speaker - they work form a 9V PP3 battery or for better sound quality 12V transformer. I have tried to make inspirational speakers - many boys love their Xbox and Playstations so the controller is a favourite design to copy for them. Quite a few of the girls liked my tree frog design and modifyied that - lots of monkeys and elephant ones in the workshop lately!
The speakers (at bottom of photo - star in the middle) are one of my best design moments this year. You see you have to have a simple solution that 13 year olds can make easily and well - that is not an easy task!
This solution traps speaker fabric (accoustically designed) inbetween the 2 frames - the centre one having a hole with a couple of mm clearence for the speaker to glue into from behind.