Lesson Summary This learning experience will take two class periods.  In this learning experience the students will identify columns, beams and diagonal supports in the frameworks of their structures.  They will be able to explain that frameworks make structures rigid, stable and able to support loads. Teacher Background The students will learn that the arrangement of columns and diagonal supports in a framework is important in making structures strong enough to support loads.  The challenge in this lesson is to remove straws from the structure that are not necessary to help the structure support itself, dead load, and the live load placed on it.  Then the students put the live load testers on the structure and record if their structures were able to hold the live load.  The students will learn that vertical columns, horizontal beams and diagonal straws are all structural components.  All the necessary supportive straws make up the structure’s framework.   The framework holds the structure up and supports all of its loads. Set-up/Management Tips In this lesson the students remove straws from their structures that they think are not necessary to support the structure itself or the live load that is added to it. Demonstrate how to safely unhook and remove straws from their structures.  Demonstrate how to safely cut straws out of their structures if you choose to let students cut out straws.  Limit the groups to one pair of scissors per group.  Helpful suggestions are on page 110 of the teacher’s manual. The directions on pages 110, 111 and 112 of the teacher’s manual list specific questions and recording data procedures for this lesson. Photocopy Group Recording Sheet Frameworks located on pages 115, 117 of the teacher’s manual for the students. Photocopy optional Home-School homework sheet teacher’s manual page 119. Gather and post photographs of frameworks on the Observations of Structures bulletin board. During this learning experience displaying pictures of building frameworks can be helpful.  These photographs will be useful in the second half of this learning experience when the student learn how frameworks support the live and dead loads of structures.  The optional book Skyscraper by Elaine Landau gives some excellent examples of beams and columns, teacher’s manual page 112.  This book is not included in the kit.   The teacher’s manual sites the following websites as good framework sources: http://www.bc.edu/bc_org/avp/cas/fnart/fa267//20_sky.html http://greatbuildings.com http://skyscraper.org http://pbs.org.wgbh/buildingbig/educator/index/html After the groups have removed straws, retested their structures, recorded the new dead loads, and shared their results ask the students to add to or revise ideas listed on the Principles of Good Construction poster and the Why Do Structures Stand Up? poster. Science notebook questions and writing suggestions for this learning experience are listed below: At the very beginning of this learning experience have the students discuss and write responses in their science notebooks to questions listed on teacher’s manual page 109. Literacy Support Scientific Vocabulary The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit: structural components beam column framework