Push and Pull

Push and Pull

Introduction to physics: Children are exploring how things move in the world around them. They will investigate how they can change the speed and direction of objects by exerting more or less strength.

Objective: Children will investigate different forces, push versus pull, by thinking about how they can make an object move. 

Objective: Using soda bottles and a ball, children will discover that when objects collide they push on one another and can change motion.

Objective: Children will experiment with changing the speed (using different strengths) and direction of an object by pushing or pulling it.

Objective: Constructing a ramp, children will explore how they can increase the speed and distance of a matchbox car.

Objective: Examining real world objects, children will sort objects into groups (push, pull, or both) using a Venn diagram.

Introduction (Whole Group):

First, connect motion to what the children already know. Ask them, How do we move? Have children raise their hand and demonstrate. Next, drop a stuffed animal on the ground. Ask students, How can I make the stuffed animal move? They will think about their past experiences with moving objects to derive an answer. Then, explain that a push and a pull are both forces. Force makes an object move or stop moving. When we push something, we are moving it away from us. When we pull something, we are moving it closer to us. [Act out motions: push = palms out, push away from body and pull = two fists on top of each other, pull toward body with students]. Brainstorm: Create a T-chart, write down objects that can be pushed or pulled (objects at home, in the classroom, on the playground).

Small Group Instruction (Stations): 

PUSH: Soda Bottle Bowling: Children experiment with pushing a ball hard and soft to knock over soda bottles. They can compare a big push to a small push. What kind of push made the ball move the fastest? They will see how when objects collide (ball and soda bottle) they push on one another and can change motion.

PULL: Chair Pulley: Loop a light weight rope around the back of two chairs. Hang a small basket within the loop to send back and forth by pulling. They will experiment with pulling the rope hard and soft. What kind of pull moved the basket the farthest?

PUSH: Ramps and Matchbox Cars: Children create ramps using flat, rectangular wooden blocks and duplo legos. They will investigate how the height of a ramp can change how fast and far their matchbox car can go. They will also compare the distance and speed of the car on the ramp to using no ramp.

PUSH / PULL: Sort: Put out a paper bag consisting of various real world objects. Children collaborate and sort the objects using a Venn diagram (hula hoops). Children distinguish the objects putting them into groups: push, pull, or both.

PUSH / PULL / MOTION: Computer Games: Children play games to reinforce push, pull, and motion. 

Push: Piggy Push from Cool Math Games

Pull: Hook the Fish from Cookie

Motion: Josie Jump's Dance-athon from BBC

Reinforcement / Closure (Return to Whole Group):

Watch a video to reinforce pushes and pulls.

For further reinforcement, the next day, have children go on a scavenger hunt and try to find things around the classroom that they can push and pull.

Assessment

Rubric

mini Pulley

materials:

empty thread spool

string

2 cups

pencil

tape

Kids construct a miniature pulley and discover how wheels can help reduce friction! Students keep one cup on the ground and have the other cup suspended in the air (both attached to the pulley). They place 20 pennies in the cup on the ground. Then, they place a few pennies at a time into the other cup. How many pennies are needed to raise the cup off the ground?

Then, they remove the thread spool. They place the string connecting the cups over the pencil. They do the same experiment above (20 pennies to one cup and add a few at a time to the other). How many pennies are needed to lift the cup off the ground?

 Kids "compare the number of pennies needed to raise the cup with and without the rotating spool." Visit Education.com for more details (experiment called SHOWTIME from Janice VanCleave's book Machines for kids)!

Construction:

tape two 6 inch pieces of string to a table

insert a pencil into an empty thread spool

attach the pencil to the hanging string

cut a long piece of string (depends on height of table) and attach to both cups

Playground Science

Photo Credit: Gabriel Pollard - swing / teeter totter

The playground is a fantastic place to conduct physical science experiments. Bring the kids out to explore levers / balance, pendulums / force, ramps / friction, and simple pulleys!

Teeter Totter
1. Balance - Have a bigger kid sit on one end and a smaller on the other. The obvious will happen of course! The side holding more weight will bring the lighter side up. Now, have the larger kid scoot towards the center of the teeter totter away from the seat. What happened? By changing the placement of weight on the lever, the teeter totter will begin to balance the two weights. Have two kids sit on one side and one on the opposite. Using your science skills you gained from the above experiment, try to balance out the teeter totter to make it equal. 

Swing
1. Force and Frequency - Give a student one small push on a swing and tell them not to pump. Count how many times the swing moves back and forth within one minute. Next, give a student one gigantic push (no pumping) and record the same data. Then, have a student pump their legs with no push and count. Compare your findings. Does a small or large push without pumping produce better results than using your legs to pump? Which way produced the largest number for the amount of times the swing went back and forth in one minute? via ehow

2. Twist a swing and let it fly. Time how long the swing takes to untwist. Then, have a kid sit on a a twisted swing. Have the child extend their arms and legs outward when you let go. You'll notice that the swing's speed will slow down. By pulling weight away from your body, you're slowing down the swing. Next, try tucking all the weight inward during a spin. Did you go much faster?

3. Body Position - Try sitting, standing, and squatting on a swing during a swinging cycle. How does this affect amplitude? Visit Odec to find out! 

Slide

1. Friction - Test different toys out down a slide. What moves the fastest. Now, try splashing water on the slide. Does water increase speed? Try laying down different textures on the slide (smooth surface vs. rough) and talk about friction. Check out this awesome pdf all about ramps from Peep and the Big Wide World!

Monkey Bars or Tree

1. Create a simple rope pulley! Click here to find out how! Check out this cute video from Play Time is Essential!