Whether your art teacher gave all students in the class an assignment to make the most fantastic waterfall they could dream up or you've drawn the subject from a list of possible science projects, have no fear. You can do it. Enlist a posse (parents) so they can share skills they learnt as kids working on their school assignments and if you want to stand out from the crowd, do some research on waterfalls so you can explain both the art and science that inspired your efforts.
Shape an 45 cm (18 inch) tall tent of chicken wire that resembles an American Indian tepee as the base for your mountain. Use small sections of craft wire or pipe cleaners to hold the shape of the large cone that may resemble a volcano at this stage.
Rip newspaper into strips and begin dipping them into a bowl filled with papier-mâché; paste or a thick mix of flour and water. Place strips of soaked paper over the wire tent in random fashion. Mush and squish paper with your hands so the mountain isn't smooth -- it should look bumpy, as if it were covered in stones and rocks. Ball up some paper strips to create lumpy texture. Allow your mountain to dry thoroughly.
Dab brown, grey, white and black paint onto your model with paint brushes to make the surface of the mountain look like it is covered with stone patterns. Put the paper-covered model aside once you're happy with the way it looks so the paint can dry. Cover the mountain with a coating of clear, waterproof sealant and allow it to dry.
Paint the plywood mountain base green so it looks like a grassy field. Figure out where you want to position the mountain on the field so once you create the waterfall coming down the mountain, you can shape a stream so your model looks authentic. Use craft glue to cement the mountain to the base.
Choose from the following methods for creating a waterfall that originates at the peak of the mountain and falls to the field below: 1) Pour a thick stream of clear polyester resin or urethane from the peak down the mountainside and extend it across the field to replicate a stream or ... 2) Cut long strips of blue cellophane and glue layers of these strips down the mountainside and across the field.
Decorate your waterfall model further by gluing the plastic moss or grass across the surface of the wood base. Cluster mounds of grass and small rocks around the mountain, and outline the stream with clumps of greenery and rocks. Your model is ready for you to show it off to the teacher and the class.