We made electricity from rainwater. You need:
a bicycle dynamo
a small plactic cotainer (yoghurt container)
8 plastic spoons
hot glue
duct tape
some wooden sticks and nails
a cone (we made it with a 3d-printer)

Step 1: Making the Waterwheel

Tape the dynamo to the top of a upside-down container. Then glue the plastic spoons to the head of the dynamo. So you get a whaterwheel. Example of a container on top.

Step 2: Making a Container for the Water

Make with the sticks a frame for the cone so it is suspended about 30 cm in the air. Then hit a nail trought the button in the upper half and not the center so it topples over when you fill the cone with watter.