When the girls were working on this structure, it reminded me of the structure they built at the Lacy Table. I listened to their conversation while they were building and I could hear them refer to it too.  I could hear them say, "We can't make it too tall because it will fall over, like the one we built before."  They couldn't remember how they built it so I suggested they draw a picture.

They both worked independently drawing their picture and you can see in their pictures how they both saw their structure.

They were excited to share this with the class at the end of the day.