Levers+and+Pulleys

=Levers and Pulleys=
 * Levers and Pulleys is a 5-6th grade kit. It aims to introduce students to some fundamental ideas in physics:
 * Students...
 * Gain experience with the concept of force and the application of force to do work.
 * Gain experience with the relationships between the components of lever systems and pulley systems.
 * Gain experience with the concept of advantage as it relates to simple machines.
 * Analyze real-world tools and machines in terms of the simple machines that make them work.
 * Systematically collect and record data.
 * Use measurement in the context of scientific investigations.
 * Use diagrams to translate three-dimensional relationships into two dimensions.
 * Acquire vocabulary associated with two simple machines (levers and pulleys).
 * Apply mathematics in the context of science.
 * Use scientific thinking processes to conduct investigations and build explanations: observing, communicating, comparing, organizing, and relating.


 * The kit is divided into four investigations:
 * Levers
 * More Levers
 * Pulleys
 * Pulleys at Work

Possible Lesson Plan

 * Kits tend to have more lessons than we have time to get through. Some lessons can be combined with others, or omitted entirely. Here is where we can suggest the 10 or so lessons for fellows to get through.
 * For a 10 day session...
 * Day 1: Investigation 1.1
 * Day 2: Investigation 1.2
 * Day 3: Investigation 1.3
 * Day 4: Investigation 2.1 and 2.4 (introduce lever diagrams 2.1, have students identify lever types in lever pictures 2.4)
 * Day 5: Investigation 2.3
 * Day 6: Investigation 3.1
 * Day 7: Investigation 3.2
 * Day 8: Investigation 3.3
 * Day 9: Investigation 4.1
 * Day 10: Investigation 4.2


 * For an 8 day session...
 * Day 1: Investigation 1.1 and 1.2
 * Day 2: Investigation 1.2
 * Day 3: Investigation 1.3
 * Day 4: Investigation 2.1, 2.3, and 2.4
 * Day 5: Investigation 3.1
 * Day 6: Investigation 3.2
 * Day 7: Investigation 4.1
 * Day 8: Investigation 4.2

=Investigations= 

Investigation 1.1: Introduction to Levers
Typical Duration: 20-30 minutes
 * Overview: Students learn that levers provide a mechanical advantage, and the four parts of a lever system.
 * Points of Interest: Students make basic levers and investigate the position of the effort and the load to the fulcrum.
 * Preparation
 * Make sure dowels have erasures attached
 * Make sure ruler is marked as indicated in the teacher manual, and the binder clip is centered at zero
 * Spring measures have the fat rubber bands on them
 * Weights have rubber bands on the hooks
 * Advice
 * The teacher's manual says to use duct tape to tape the dowels to the kids' desks. DO NOT USE DUCT TAPE. Masking tape will work fine for this.
 * Be sure to use the fat rubber bands for the weights and the spring measures. Skinny rubber bands will either snap or slide around.
 * Vocabulary
 * Lever - a simple machine that people use to gain a mechanical advantage
 * Lever arm - a stick or beam that is free to pivot at a point
 * Fulcrum - the point where the lever arm pivots
 * Load - the mass lifted or resistance overcome
 * Effort - the force needed to move the load or overcome resistance (measured in Newtons)
 * Content
 * Levers provide advantage by reducing the effort needed to lift and move loads.
 * Levers have four parts - the lever arm, fulcrum, load, and effort.
 * Demo ideas
 * Media Clips and Links
 * Extensions
 * Other useful additions to this lesson.

Investigation 1.2: Lever Experiment A
Typical Duration: 50 minutes
 * Overview: Students learn that the amount of effort applied decreases as the position of the effort moves away from the fulcrum.
 * Preparation
 * Photocopy student sheet No 4 (Lever Experiment A). If you want, pre-label the X and Y axis with values of 0 - 25 cm (X) and 0 - 10 N (Y).
 * Be sure that all of the equipment from Investigation 1.1 is in good shape and ready to go.
 * Advice
 * Be sure to tape the dowel so only about an inch is hanging over the desk. If too much more is hanging over, the dowel will probably get pulled off of the desk.
 * Remind students that the position of the LOAD does not move (some students try to move both the load and the scale).
 * Some students will try to record the effort using the "grams" side of the scale. Remind them that they want to use the number on the "N" side.
 * Tell students to write down the numbers they observe in the "scale" column and to ignore the other column (add 0.5N) until the end.
 * Some students may not remember how to graph a point using x,y coordinates. It helps to graph each point using different color markers.
 * Vocabulary
 * Two coordinate graph - show relationships between two variables
 * Advantage - a benefit obtained by using a lever (or other simple machine)
 * Content
 * The farther the effort is from the fulcrum, the easier it is to lift the load
 * Demo ideas
 * Media Clips and Links
 * Extensions
 * Other useful additions to this lesson.

Investigation 1.3: Lever Experiment B
Typical Duration: 50 minutes
 * Overview: Students learn that the amount of effort applied increases as the position of the load moves away from the fulcrum.
 * Preparation
 * Photocopy student sheet No 6 (Lever Experiment B) and No 5 (Response Sheet - Levers). If you want, pre-label the X and Y axis with values of 0 - 25 cm (X) and 0 - 10 N (Y).
 * Be sure that all of the equipment from Investigation 1.1 is in good shape and ready to go.
 * Advice
 * Remind students that the position of the EFFORT does not change (some students try to move both the load and the scale).
 * Content
 * The further the load is from the fulcrum, the harder it is to lift the load
 * Demo ideas
 * Media Clips and Links
 * Extensions
 * After completing experiment A and experiment B, have the students look at their graphs and remind them that
 * The further the effort is from the fulcrum, the easier it is to lift the load
 * The further the load is from the fulcrum, the harder it is to lift the load (or the closer the load is to the fulcrum, the easier it is to lift the load).
 * Have the students work on the response sheet. The should find that one of the levers will be easier to use, based on the two relationships they defined above. If necessary, set up both lever systems, and have the students try it out themselves.

Investigations 2.1, 2.3 and 2.4: Lever Diagrams
Typical Duration: 60 minutes
 * Overview: Students learn that there are different types of levers, and investigate real-world examples of these lever systems.
 * Preparation
 * For each class: Photocopy Teacher sheet No 7, 8, 9, 13, 14, 15
 * For each student: Photocopy student sheet No 16 (Lever Pictures A), 17 (Lever Pictures B), and No 12 (Levers at Work) with the names of the objects whited out (so that students can write their own objects).
 * Advice
 * Introduce the different lever classes. Ask the students if there is a different way for you to arrange the load, fulcrum, and effort. Show the students the diagrams for each lever system //with// the pictures (ie sheet No 7 with No 13, etc.)
 * Pass out the student sheets. Have the students identify the lever class for each of the pictures in student sheet No 16 and 17. After the students are done (some will do this very quickly), go through the sheet. Have the students raise their hands showing the number of fingers to indicate which class of lever they think is in the picture.
 * When students are done, have them walk around the room with sheet 12, draw the objects, and figure out what class they are. You can make this like a scavenger hunt, where the students who find the most objects win a prize (ask the teacher for prize ideas). Have the students give you examples of levers they found around the classroom.
 * Content
 * Class 1 levers have the fulcrum in the middle - EFL or LFE
 * Class 2 levers have the load in the middle - ELF or FLE
 * Class 3 levers have the effort in the middle - LEF or FEL
 * Many every-day objects contain levers
 * Demo ideas
 * Media Clips and Links
 * Extensions

Investigation 3.1: One-Pulley Systems
Typical Duration: 50 minutes
 * Overview: Students learn that there are two types of pulley systems.
 * Preparation
 * For each class: Photocopy Teacher sheet No 21
 * For each student: Photocopy student sheet No 18 (Pulley Diagrams) and No 19 (Response Sheet - Pulleys).
 * Be sure that all of the equipment needed is in good shape and ready to go.
 * Advice
 * Students know that levers can be used to provide mechanical advantage. Ask they how they would move a really big object, like a whale. Would they want to use a lever, or is there another simple machine available?
 * You don't need to use a big book to hold the ruler. Just make sure it is taped to the desk so that only the binder clip is hanging over the edge.
 * Students only need to do the first part of sheet 18, and should draw the single fixed and single movable pulley systems at the bottom of the page
 * Vocabulary
 * Pulley - a wheel with a grooved rim in which a rope can run to change the direction of the effort that lifts the load
 * Fixed pulley - the wheel is attached to something above the load (the pulley is fixed to a point)
 * Moveable pulley - the wheel is attached to the load (the pulley moves on the rope)
 * Mechanical advantage - reduces the effort needed to lift a load or overcome a resistance
 * Directional advantage - a change in direction that results from passing a rope through a pulley
 * Content
 * A single pulley can be used to lift a load
 * Single fixed pulleys change the direction of effort (pull down instead of up)
 * Single movable pulleys reduce the effort needed to lift the load
 * Demo ideas
 * Media Clips and Links
 * Extensions

Investigation 3.2: Two-Pulley Systems
Typical Duration: 50 minutes
 * Overview: Students learn that there are two more types of pulley systems.
 * Preparation
 * For each class: Photocopy Teacher sheet No 22
 * Be sure that all of the equipment needed is in good shape and ready to go.
 * Advice
 * Students know the single-fixed pulley system and the single-movable pulley system. Ask them if they can think of any other pulley systems. Suggest that they use an additional pulley.
 * Give each group two pulleys, a rope, the ruler with binder clip, and the load. As them if they can think of a way to use the two pulleys together to lift the load.
 * Students should draw the double SF/SM or double SM/SF pulley systems at the bottom of student sheet 18. Ask them to fill out response sheet 19.
 * Vocabulary
 * Simple machine - a basic device that provides mechanical or other advantage
 * Content
 * Two pulley systems provide greater mechanical advantage than a one pulley system.
 * Demo ideas
 * Media Clips and Links
 * Extensions

Links
[|FOSSweb Levers and Pulleys website]. For teacher resources, click "For Parents and Teachers" (bottom left), then "Teacher Resources". There are teacher prep videos, pdfs of all the handouts, etc. Home page Ice cream