Domesticity

Today I had the gift of a large block of math time that was just for the Herons. We had wrapped up our fractions unit on the Friday before Wolf Ridge and we'll begin our next unit on area and perimeter on Tuesday. An hour and a half for a math lesson…I had been waiting for just such an opportunity.

Using nothing but newspaper and tape, the herons created a geodesic dome that we could all fit inside. We had to roll tubes of newspaper carefully to make them strong. Then we had to measure the tubes precisely and cut them to 66cm or 71cm. I modeled both of these steps — but then I handed over the construction instructions to the students for them to figure out.

Each child worked to find his or her role in the project. Some excelled at rolling tubes and that became their job. Others struggled to puzzle out the diagrams in the instructions and then directed others as to what to do. Some measured, others tallied so that we didn't make too many of one or the other length. Still others were quality control monitors (their term, not mine) who made sure that the tube lengths were consistent (at first they weren't.) One child volunteered to tape the work and make a movie.

As the dome began to rise, we had to problem solve together. What was the best way to join the struts? Why did it seem like the struts weren't long enough? Did it matter where we put our stronger struts?

After the thrill of creating the dome, we took a moment to examine it. What shapes did we see? Where was there stress on the form? Which struts were "load bearing?" Why didn't it collapse? Where was there compression? Where was there tension? At first, students thought that the struts parallel to the floor weren't as important as the vertical ones — until someone pointed out that the triangles all fell down flat before we had the horizontal ones in place.

Some students want to turn our dome over and create a geodesic sphere. Others wanted to start a business making domes for other classrooms.

Some kids wanted the instructions to try one at home. Here they are: http://www.pbs.org/wgbh/buildingbig/educator/act_geodesic_ho.html