Exploring Science ConceptsUnit: Physical ScienceStrand E Forces and Motion

Grade TwoNovember 2010

Inquiry

Hands-On Active Learning

Multisensory Learning

Student-to-Student Interaction

Discourse and Reflective Thinking

Reading- FOSS Science Stories

FOSS Web

FOSS Instructional Pedagogies

Three Investigations- each with subset of activitiesDesigned for students to:Investigate materials constructively during free exploration and in a guided discovery mode.Solve problems through trial and error & develop persistence in tackling a problem.Explore concepts of balance, counterweight, and stability.Observe systems that are unstable and modify them to reach equilibrium.Discover ways to produce rotational motion & construct and observe toys that spin.Explore and describe some of the variables that influence the spinning of objects. Observe and compare rolling systems with different-sized

wheels. Explore and describe the motion of rolling spheres. Acquire the vocabulary associated with balance and motion.

Balance and Motion Overview

Science Concepts:• Objects can be balanced in

many ways.• Counterweights can help

balance an object.• A stable position is one that is

steady; the object is not falling over.

• The way an object balances can be changed by counterweighting.

• The position of an object can be described by relating its locations to another object.

Purpose:Students will…• Discover numerous ways to balance

tagboard shapes.• Find ways to balance a pencil on its

point, in stable positions.• Explore the concepts of balance,

counterbalance, counterweight, and stability by balancing tagboard shapes, making mobiles, and engaging in other balancing projects.

• Communicate observations and comparisons of balanced objects, using precise vocabulary.

Investigation 1 BalanceFour Parts

Focus:• Objects can be balanced in

many ways.• Counterweights can help

balance an object.• The way an object balances

can be changed by counterbalancing.

Task:1. Introduce the crayfish2. Balance on finger3. Can crayfish be balanced in

other ways?4. Introduce clothespins , allow

inquiry, suggest moving pins in different locations. Get crayfish to balance on its noselike projection or rostrum.

Investigation 1 BalancePart 1: Trick Crayfish

5. Call to rug and ask:- What did you do to get the crayfish to balance on its nose?- Does it matter where you put the clothespins?

6. Introduce “counterweight”- use to balance in new ways7. Challenge students to find new ways to balance their

crayfish.8. Wrap Up:

- Discussion- Word Bank- Content Chart

Part One Trick CrayfishInvestigation One: Balance

Focus:• A stable position is one that

is steady; the object is not falling over.

• The place on which an object balances is called the balance point.

• Counterweights should be placed low on an object in relation to the balance point.

Tasks:1. Revisit balancing of crayfish-

introduce as a stable position; demonstrate what happens with a gentle push

2. Introduce new shapes- challenge to balance shapes on end of craft stick rather than finger

3. Discover stable & unstable positions using one/two clothespins with each shape.

Investigation 1 BalancePart 2: Triangle and Arch

4. Ask:- Can you get it to balance

another way?- How many ways can you make a

stable position using only one clothespin for a counterweight?

- Can you balance both objects at the same time?

- Try working with a partner, together can you find new ways to make stable balanced systems?

5. Assess Progress :- Use Stable Positions Sheet

- If needed, redistribute materials and allow students to set up the systems shown in the pictures to see if they are stable

6. Wrap Up:- Word bank- stable, arch, triangle,

balance point- Concept Chart- How can you tell by

looking at a picture if it is a stable system?

Investigation 1 BalancePart 2: Triangle and Arch

Focus:• Counterweights should be

placed low on an object in relation to the balance point.

• The position of an object can be described by relating its location to another object.

Tasks:1. Review Part 2- recall stable systems and

to think about where clothespins were put.

2. Challenge students to balance tagboard pencil on craft stick using clothespins; remind students to test stability.

3. Call to rug- discuss balancing , ask:- Where did you put the clothespins to

get a stable system?- Can you get a stable system using no

clothespins? One? Two?- Where did you place the

counterweights to get a stable system?

Investigation 1 BalancePart 3: The Pencil Trick

4. Give the real pencil challenge- balance a sharpened pencil on its point on the craft stick

5. Introduce the wire- wire can be attached to the pencil, but not used to tie pencil to the craft stick

6. Assess Progress via teacher observation; provide hint if needed; allow students to share successes.

7. Wrap Up:- Discussion:

How might you balance a stick on top of a 2-liter soda bottle?How could you balance a chair on a tight rope?

- Word Bank- Content Chart: What is the trick

to balancing an object on one point?

- Read science story, Make It Balance!

Investigation 1 BalancePart 3: The Pencil Trick

Science Concepts:•Objects can be balanced in many ways.• Counterweights can help balance an object.• A stable position is one that is steady; the object is not falling over.• The way an object balances can be changed by counterweighting.• The position of an object can be described by relating its locations to another object.

What we learned from Investigation 1 Balance

Science Concepts:1. Objects and systems that turn on a central axis exhibit

rotational motion.2. The amount and position of mass affect how an object

rotates.3. A push or pull (a force) is needed to initiate rotational

motion in objects and systems.

Investigation 2 SpinnersThree Parts

Inquiry Question: • How can spinning tops be changed?Investigation Summary:• Students make tops from plastic disks and shafts, and spin them.

After finding the arrangement of parts that produces the best top, they make tops from other materials.

Science Content:1. Objects and systems that turn on a central axis exhibit rotational

motion.2. You need a force to start a top spinning.3. The amount and position of mass affect how the object rotates.

Investigation 2 SpinnersPart 1 Tops

Important Points to Lesson:1. Do not tell students how to make tops- the challenge is how to

use the materials to make a good top.2. Discuss Top Progress (#6) introduce “rotating”3. Challenge students further:

• Best design for a top that spins a long time?• Best design for a top that spins fast?• Does it make a difference if big or small disks are used?

4. Assess Progress (#10)5. Wrap Up- word bank, concept chart6. Science Stories Push or Pull?

Investigation 2 Spinners

Part 1: Tops How can spinning tops be changed?

Inquiry Question: • How can a spinning object be kept in motion?Investigation Summary:• Students use disks and a length of string to make zoomers.Science Content:1. There are different ways to initiate rotational motion.2. The motion of an object can be changed by pushing or pulling.3. Tops and zoomers both spin, but in different ways.

Investigation 2 SpinnersPart 2 Zoomers

Important Points to Lesson:1. Review type of motion tops make- indicate zoomers also rotate

(spin) when in motion.2. Demonstrate the zoomer in action3. Demonstrate knot tying4. Some students will have difficulty getting zoomer assembled and

going; let them work at the problem for a while before assisting5. Wrap Up- word bank, concept chart6. Science Stories Tools and Machines & the story Move It, But

Don’t Touch it

Investigation 2 Spinners

Part 2: Zoomers How can a spinning object be kept in motion?

Inquiry Question: • How can air start an object spinning?Investigation Summary:• Students make twirlers (flying spinners) that rotate by air

resistance, first modifying soda straws with wings, and then making twirly birds from paper and paper clips..

Science Content:1. Variations in design can influence the rotational motion of

spinning objects.2. Air resistance can act as the force that initiates rotational

motion.

Investigation 2 SpinnersPart 3 Twirlers

Important Points to Lesson:1. At start review spinning motion of tops and zoomers. Point out

a force had to be applied to start the spinning motion.2. Challenge students to get straw to spin- let them discover3. Limit directions by you on how to assemble twirlers4. Test twirlers5. Use questioning (#8 #9) to assess progress6. Wrap Up- word bank, concept chart7. Science Story Things That Spin

Investigation 2 Spinners

Part 3: Twirlers How can air start an object spinning?

Science Concepts:1. Things move in many different ways.2. Wheels and spheres roll down a slope.3. Axles support wheels.4. Wheel-and-axle systems with wheels of different sizes roll

toward the smaller wheel.5. The amount and location of an added weight can change the

way a system rolls.

Investigation 3 RollersThree Parts

Inquiry Question: • How can a wheel-and-axle system be changed?Investigation Summary:• Students set up cardboard ramps down which they roll plastic disks.

They put the disks on slim shafts to make wheel-and-axle systems. They try all kinds of configurations of wheel size, axle length, and axle position to get the rolling systems to perform a variety of tricks.

Science Content:1. Wheels roll down a slope.2. A slope is a surface that is higher on one end.3. Axles support wheels.4. Wheel-and-axle systems with wheels of different sizes roll toward the

smaller wheel.

Investigation 3 RollersPart 1 Rolling Wheels

Important Points to Lesson:1. At start identify rotating(spinning) as one kind of motion and

how it is identified.2. Discuss early results using ramps and large wheels(#6) before

introducing axles3. After making tricky rollers provide small wheels4. Encourage sharing of results and collaboration5. Show and Tell (#12) Discuss similarities in design- identify roll

fast, farthest, slowest6. Wrap Up: word bank and concept chart

Investigation 3 Rollers

Part 1: Rolling Wheels How can a wheel-and-axle system be changed?

Inquiry Question: • Can we predict the behavior of a rolling cup?• What happens if weight is added to a rolling-cup system?Investigation Summary:• Students roll paper cups down ramps. They observe the way cups roll and

use the predictable curved rolling path to meet challenges. They put cups together to make them roll straight and weight them in various ways to see how weight affects rolling.

Science Content:1. Cups roll in the direction of the smaller end.2. To roll straight, two cups can be taped together so the ends are the same

size.3. The amount and location of an added weight can change the way a

system rolls.

Investigation 3 RollersPart 2 Rolling Cups

Important Points to Lesson:1. Review kind of motion wheels make-rolling2. Maintain inquiry nature of cup rolling task.3. Pose questions (#4) prior to “Park the Car Problem”4. Try to go straight- let students try their ideas5. Add weight (coins) to straight roller- discuss (#13)6. Wrap Up: word bank, content chart7. Science stories Rolling, Rolling, Rolling!

Investigation 3 Rollers

Part 2: Rolling Cups Can we predict the behavior of a rolling cup? What happens if weight is added to a rolling-cup system?

Inquiry Question: • How can we make a runway system that will keep a marble rolling?Investigation Summary:• Students roll marbles in cups and down runways. They work with the

flexible runways to make the rolling marbles do tricks. As a culminating experience, students work together as a class to connect the runway sections to make one long runway through which a marble can roll nonstop.

Science Content:1. Spheres are round in all directions and roll in all directions.2. A runway must be high at the start and low at the finish for a

sphere to roll the complete length.3. Spheres roll down a slope.

Investigation 3 RollersPart 3 Rolling Spheres

Important Points to Lesson:1. At start review rolling motion of wheels and cups; contrast with shape of a

sphere.2. Free exploration- challenge students to find out how marbles roll in the

runways.3. Marble tricks- care with foam runway4. Teams of students may work together to connect their runways.

Demonstrate how to connect two runways. 5. Discuss key points before building LONG runway6. Keep it trial and error till success is met.7. Assess Progress with Marble Runways worksheet8. Wrap Up: word bank and concept chart9. Science stories Strings in Motion FOSS Web animation

Investigation 3 Rollers

Part 3: Rolling Spheres How can we make a runway system that will keep a marble rolling?

Part 1: Trick Crayfish Wrap UpDiscussion Questions:Where should you put clothespins on a paper crayfish to get it to balance on its side?How could you get the crayfish to balance straight up and own on its tail?

Word Bank: crayfish, balance, clothespin, counterweight

Content Chart- lists statements that summarize knowledge acquired from investigations- How do you know when something is balanced?- Think about all the different ways you balanced the crayfish. Is there anything you noticed that is always the same?

Formative Assessment-Part of the shape resting on the stick is the balance point. - small black rectangle is end of craft stick