I read a WCYDWT blog at: http://webmaths.wordpress.com/2010/05/27/wcydwt-bento-box/
Since my comment is pending moderator “intervention”, I thought I would post my response here just in case it doesn’t make it to the original blog. Here it is:
I will be interesting to see how your plan goes. To go real Dan Meyer on you (not that I am an expert), you could have also tried just showing the bento box to your students and asking them what they see. Kind of like asking them how long a container will take to fill without providing any other info ☺. Perhaps you can get enough disposable containers to give one to each student and see what they do with it. I bet they would come close to what you planned, but they may also come up with something different and/or better! One other comment: it might be interesting to do a bit of cross-discipline education – that is, giving some background on what a bento box is, what culture it comes from, why, etc.