Scrimshaw Not really but working in beef bones gives a similar affect to ivory.
Get some beef bones. 
Clean them a little.
Cut the knuckles off.
Split them on a band saw, preserving the flattest side.
Scrape the marrow out for your dog.
Cook them outside (they stink) or by yourself. In a pot with some detergent and lots of bleach. About 1/2 cup to a litre of water.
Rough them out with band-saw if they are larger shapes.
Small shapes, hot glue the bone to a larger piece of wood to safely cut the shape out.
Shaping and smoothing the bone.
Wrap some 1200 grit wet and dry carborundum paper around a stick or steel ruler to shape the bone. Keep everything under the tap with dripping water and the bone will shape quite quickly
Drawing Patterns.
Draw patterns on the bone with a sharp pencil and then sharpen a nail on a grinding wheel so it is very sharp.
Carefully follow the pencil drawing with the sharp steel poined implement.
Using a pair of pliers squeeze a drop of red blue of black ink from a pen refil and rub the ink into the scratches before polishing.
Don't press hard as the heat will soften the glue quickly and the bone will come off the stick.
Use the jewellers rouge stick sparingly as too much does not polish more, it just makes a mess.
Wear safety glasses have no lose clothes and contain hair.
For the teacher be aware that if the bone comes lose the student will instinctively bend to pick it up and on some occasions go under the spinning wheel.
This is just another material that is cheap (The George Town butcher donated all our bones) and easy to create objects from. It is easy for students to use even if it is a bit smelly to prepare and cut. Students love the overall affect and it lends itself to design briefs where multiple materials are used. There can be discussions as to why we use beef bone instead of whale and ivory and the discussion can lead into the whole idea of conservation of whales and elephants.