Today the class continued their discussion of tension and compression. Dr. Love explained the factors involved in these processes and how they influence both the tension and compression properties. The students visualized these concepts by constructing trusses on the computer and learned the terminology associated with these activities: such as node and members. The students also learned about the effects of the load and the direction that is placed on the structure and how much tension and compression is applied to the structure.
Afterwards, the students put their newfound knowledge to good use by using it to play a game. The students challenged each other and constructed different structures, using the same computer program as before, to see which bridge could withstand the maximum and minimum tension and compression, respectively. You can find the rules to the game here.
After completing the activities on the computer, the students then were given the challenge to build a structure out of straws that could hold up a maximum of 150 marbles. The score was determined by the number of marbles multiplied by the height of the structure. The concepts they learned earlier, including symmetry, balance, tension, compression and load, were all needed for this activity.
http://www.shodor.org/succeed/curriculum/EIT/pages/strussdir/strussp7.html