I will begin this lesson by reviewing the Friction Photos PowerPoint from the previous lesson, What is Friction? Allowing students to review the Friction Photos activates their background knowledge. As we review each picture, I will ask students to share how friction is occurring in each situation and how friction might affect how each material works together. I will inform students that in most situations where friction produces heat, the material gets worn down over time.
I will lead a discussion about how different materials can be worn down over time by friction. I will share examples with the students like their pencil eraser and car tires. Once complete, I will ask students to brainstorm some ideas for preventing friction and list them in their science journal.
Once students have completed their lists, I will inform students that today we will be causing friction with chopsticks. I will instruct students to get into pairs and each pair will receive a pair of chopsticks. I will prompt students to rub the chopsticks together briskly.
I will ask them to explain what they think we can do to reduce the amount of heat being produced through friction while still rubbing the chopsticks the same way.
Next, I will display different items to the students such as water, wax paper, notebook paper, foil, and vegetable oil. I will explain to the students that materials that are used to reduce friction between to surfaces are called lubricants. Each item listed on the data sheet will serve as a lubricant. I will ask students to predict which lubricant will reduce the most friction.
Next, I will pass each pair a piece of paper. I will guide them into wrapping the paper around one of the chopsticks and instruct them to continue to rub the chopsticks together. I will ask students to describe how the amount of heat being produced has changed with the paper. I will direct them to record their observations in their science journal.
Students will then receive wax paper, aluminum foil, vegetable oil, and water. I will instruct them to use each lubricant one by one, ending with the vegetable oil. I will remind students to continue recording their observations in their journal.
To wrap up the lesson, students will complete the Chopsticks and Friction worksheet. Next, students will transition to the carpet for a whole group discussion. Students will be given the opportunity to share and compare their results based on the data recorded on their recording sheets.
I will ask students to share which materials did not help to reduce heat produced through friction and which materials were most effective in reducing the heat produced by friction. Lastly, I will ask students to share what they learned from ideas that did not work to reduce heat produced by friction.