Building a honeycomb: Here's a fun collaborative project we did at our Gellin' with Geometry Family Math Night event. It was a great way to have everyone contribute. A fun family math night activity! It can also be done with a regular classroom or buddy classes! Here's a video version of the process and the math: http://www.youtube.com/watch?v=TFvRc3CqXv0 www.FamilyMathNight.com
Use this template for students to write their estimates for estimation jars. Much better than a ripped up piece of paper! I love using estimation jars to teach math skills, as well as at Back to School Night, Open House, and other events with families.