Entry 7- Simple Machines

SIMPLE MACHINES

Students will learn that a simple machine is a tool that uses force to make work easier.  An inclined plane, lever, pulley, and a wheel and axle are examples of simple machines.  Children will learn how these machines make work easier.  While machines have many moving parts, a simple machine has none or few moving parts.  A force is a push or pull that can change the way something moves.  Any push or pull is a force. Review with children that heavier objects require more force to move.   Some objects are so heavy that people need machines to use them. A simple machine can change the direction or significance of a force in different ways to make work easier. It can change the way a force is used to make it more effective.  A ramp, or inclined plane, is a simple machine with a slanted surface. It helps people and things move between higher and lower places. A lever is a simple machine that consists of a bar that rests on a fulcrum, or a point that does not move. A lever can also help lift up heavy loads. A wheel and an axle work together to make a simple machine. Explain that a wheel turns around a rod, called an axle. A wheel and axle can help move things faster or easier, and also help things turn. A pulley is a simple machine that has a rope or cable that goes over a wheel. A pulley helps people lift things up and change the direction of their force. You pull on a rope to make the load go up. You can also connect pulleys together, creating a combined pulley that requires less than half the force otherwise needed to lift up a load. Combining simple machines can also help to make work easier (CONTENT).

After reading, Simple Machines from our Reading Street series at school, we will discuss the simple machines that we have encountered in everyday life. Examples might include a slide, flagpole, stapler or pencil sharpener.  Students will identify and list or draw simple machines found around the classroom. (DOK 1) Students will classify the simple machines by type. (DOK 2)  We will also discuss that these are not “new” inventions but that people have been using this technology for thousands of years.  Being that we have discussed transportation from “then & now” we will learn how the Allegheny Portage Railroad used these inventions to drastically reduce the travel time from Philadelphia to Pittsburgh.  We will then identify the simple machines used for the railroad (DOK 2).  Upon completing our content and discussions, students will then go through 3 stations where they can make their own simple machines.  Constructing the simple machines and adjusting them to meet needs. (DOK 3 & 4) (CREATIVE ACTIVITY)(Standards 3.2.1.B1, 3.2.1.B7, 8.1.1.B, 8.3.1.C)

Station 1: Ramping Up – Students will create ramps using books and building blocks.  They will then take cars and cylinders and roll them down the ramps.  I will ask them to measure the distance it travels and then ask them to change the steepness to see how the distance changes. (Revising - DOK 3) Students will share their findings (DOK 4).

Station 2: Pulley Message System – Students will make their own pulley.  They will take two small spools of thread and put a pencil through the center. Then tie the ends of a length of string together to create a loop.  Have two students hold the pencils and spools and spin them slowly to create a pulley system. Then have another student write a message and attach it to the thread using a paper clip.  Use the pulley to pass the message from one person to the other (DOK 4).

Station 3:  Give a Lift – Tape a pencil to a table.  Then place a ruler on top of the pencil to create a lever.  Place an object on one end of the ruler and press down on the other end to lift the object up.  Try using objects of different weights.  What happens? (DOK 3)  Is it easier or harder to lift heavier objects?  Then have your child move the ruler so that the fulcrum is closer or farther away from the load.  When does it become easier or harder to lift the load?  Does the load ever become too heavy for the lever, and if so where is the fulcrum? (Investigating, drawing conclusions and creating - DOK 3 & 4)

                                    

Each station will provide students with the opportunity to create and apply the basic concepts of the simple machines. (DOK 4)

Domain 1a, 1b, 1c, 1d, 2a, 2b, 2c, 2d, 3a, 3b and 3c