Building

Building & Balancing

Objectives:

Students will:

build a working system
experiment with balance and symmetry
use a tool to gather data
apply working knowledge to create a new tool

Materials: Using K'NEX pieces.

Per Group:

- Rods: 11red, 4 gray, 2 yellow, 8 white, 8 green

- Connectors: 2 blue 6 purple, 10 red, 1 orange, 4 light gray, 6 dark gray, 2 white

- Misc.: Chalk, paper clip, small pencil

Construction:

construct the balance with the pieces and picture provided

Activity #1 Heavy or Light?

"First put a small object on one side of the balance. Then, put a K'NEX piece on the other side."
" Which K'NEX are heavier than your object?"
" Which are lighter?"
" Sort your K'NEX into two piles heavier and lighter."
Have your students combine their data and rank the weights of the classroom objects

Activity #2 Adjusting the Balance

- "Lets see what happens if we change one part of the balance at a time. Does it still work as well?"
- Encourage students to alter the balance changing only one K'NEX piece at a time. With each change they          should observe their results.
- Students might change:
    - the length of arm of the balance
    - the length of the Rod that the pan hangs from
    - the position of the orange Connector along the red Rod
    - the size of one pan
- "How did your changes affect how your balance works?" Activity #3 Using the Balance

                     - "Try using your balance to test the weights of some K'NEX pieces."
                     - " See if it makes a difference where on the pan you place the pieces."
                     - Ask the students to share their findings regarding how much different pieces weigh in relation to each other.

Activity #4 Finding Equal Weights

              - "Try weighing K'NEX pieces on your balances. Find out how many smaller pieces it takes to balance a heavier
                        piece."
                     - " Try lots of combinations, and be sure to record your data!"
                     - Have students chart their findings on the blackboard.
                     - Help them to find equivalent weights.

Resource:

- K'NEX Instructions Booklet by K'NEX Industries Inc. 1995