Build a LEGO Balance. LOVE this idea for our students with special learning needs. They often love legos and this is a great activity they can complete from beginning to end. Understand how to read a scale AND how to build one. Awesome!! Get all the directions with lots of pics at: http://frugalfun4boys.com/2015/05/04/build-a-lego-balance/
LEGO Building Challenge: Machines Paper. How to build a working LEGO paper crimper and a machine that draws circles. Great STEM challenge!
LEGO Gravity Rollers: A Fun Contraption That Propels Itself!