Kindergarten: Magnets and Materials
Click Kindergarten: Magnets and Materials to access the lesson for the Kindergarten—Force and Motion strand.
Click Kindergarten: Magnets to access the book.
Take a moment to read the book. The main concepts are that different types of magnets exist and that some materials are magnetic while others are nonmagnetic.
How do you know if something is magnetic? Nonmagnetic? Create a T-chart and list items that are magnetic on the left side and nonmagnetic on the right side.
Grade 1: Magnets Push and Pull
Click Grade 1: Magnets Push and Pull to access the lesson for the Grade 1—Force and Motion strand.
Click Grade 1: Magician Nicki Reveals Magnetic Magic Tricks to access the book.
Take a moment to read the book. The main concept is that magnets exhibit pushing and pulling forces.
What caused the marbles to stick together? What caused the rings to separate or float? How did Nicki make her magic tricks work?
Grade 2: Magnets in Everyday Life
Did you know that a magnet helps make a small hobby motor work?
Click Grade 2: Magnets in Everyday Life to access the lesson for the Grade 2—Force and Motion strand.
Take a moment to read through the Teacher Note, Advance Preparation, Safety Alerts, Teacher Demonstration, and Teacher Instruction in the lesson. The teacher demonstrations show students ways magnets affect items they use in their everyday lives. For example, how is the small motor like the motor you built during Explore?
Click Grade 2: Popular Magnetics: Magnets in Everyday Use to access the book.
Take a moment to read the book. The main concept in second grade is that magnets are used in everyday life.
Did you know that magnets are a part of so many things? What uses of magnets surprise you?
Grade 3: Forces at Work
Click Grade 3: Forces at Work to access the lesson for the Grade 3—Force and Motion strand.
Click Grade 3: Forces at Work to access the book.
Take a moment to read the book. The main concepts for third grade are the forces of magnetism and gravity, how to measure force using spring scales, the concept of work, and the use of simple machines.
You may have noticed that this book is content heavy. It may be best to read one section at a time and to stop often for discussion and reflection. Allow students time to ask questions or discuss the concepts in the book with a classmate.
What is a force and what are some examples of force? How do we measure force? If you said, "We measure force using a spring scale," you are correct. Locate a spring scale so you can practice using it.
- Make sure the scale is zeroed. As some spring scales are used repeatedly, their springs will stretch. You can zero the scale by sliding the number line so that the base of the spring reads zero without anything hanging from the hook. Some scales will require you to twist a turnstile that will place the base of the spring at the top of the number line.
- Check to make sure the scale will work for the task you assign to students and that the force you are measuring is not greater than the capacity of the scale. If the object you are trying to measure cannot be held by a hook, simply poke a small hole into a plastic bag and drop the object into the bag. Hang the bag from the hook to measure the force.
- When using a spring scale to measure forces in motion, take the measurement once you have the item in motion, not right as you begin to pull. Remember to measure force using newtons.
View the video to review how to use a spring scale.
Refer to the Content Resources document for more information on how to use spring scales.
What does work mean in science? Work means we have used force to move an object to a new location. What are some examples and nonexamples of work?
Let's refer back to the tasks on RM 1 from the Explore activity. Nonexamples of work include pressing on a wall and table or the teacher's desk using only your pinkie finger. Most likely, none of the tasks caused anything to move even though a great amount of force may have been used. All of the other tasks used force to move an object to a new location; therefore, work was accomplished in those tasks.
In elementary school, we do not do calculations with students to determine how much work is accomplished. That step will occur in grade 8, specifically 8 (6)(A). However, for your knowledge, work is calculated by how hard and how far you push (or pull) using the equation Work = Force x distance (W = Fd). You can exert a great deal of force (pushing on a wall), but there is no work done if the object to which the force is applied does not move. The force and the motion must be in the same direction (motion is parallel to force).
Sometimes we can use tools called simple machines to lessen the amount of work or to make the amount of work feel easier. For example, wheels and axles on wagons, cars, bicycles, and wheelbarrows help us move and carry objects from place to place. We use pulleys to raise flags up flagpoles.
Is it possible to measure the strength of the pushing or pulling forces in these activities? Yes, you can use a spring scale.
Grade 4: Effects of Force
Click Grade 4: Effects of Force to access the lesson for the Grade 4—Force and Motion strand.
Click Grade 4: Forces among Us to access the book.
Take a moment to read the book. The main concepts for grade 4 are the forces of magnetism, gravity, and friction; how to measure force using spring scales; and how to conduct an experiment.
Just like grade 3's book, this book is content heavy. Students may be less familiar with expository text and will need to stop often to ask questions and reflect on what they have read to fully understand the concepts.
Forces are pushes or pulls and include magnetism, gravity, and friction. How do magnets behave when they repel or attract? They either push away from each other or pull together.
Gravity causes a pull between two objects. For example, everything on Earth pulls toward its surface. Earth has a huge gravitational pull because it has an enormous mass.
Friction is a force that occurs when two objects rub against each other. How do people experience friction in their everyday lives? We rub our hands together when they are cold or wear shoes with rubber soles to prevent us from slipping.
We can use spring scales to measure these forces in newtons.
How do we begin an experiment? We begin an experiment with a question, of course! How do we answer that question? We formulate a hypothesis, or a prediction that expresses what we think will happen in the experiment. We repeat the procedure more than once to improve the reliability of our results. If the measurements are similar for each trial, we know that we have reliable results.