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Science: Science on the Sandlot

I. Introduction - rationale, goals, target audience
Have you ever wondered about those raised red cotton stitches on a baseball? Sure, they hold the cowhide together, but did you know they also teach an interesting lesson in aerodynamics? Why do some hitters choke up on the bat? Why do some players wear batting gloves? Why is every hit not a home run? Why are baseball gloves made of leather? What's the major league math behind wood versus aluminum bats? Find answers to these questions in the physics of friction, center of mass, forces of motion and other concepts that become fascinating factors in a batter's ability to launch the long ball. Maybe Isaac Newton couldn't snag a pop fly, but he can coach you in the surprisingly scientific feat of catching up to a 100 miles per hour fastball in just 0.4 seconds and sending it into orbit! Step out of the dugout and up to the plate as the Baseball Hall of Fame delivers a lively look at science on the sandlot.

II. Objectives - in completing this lesson, students will:
A. Examine historical aspects and physical forces involved in playing baseball, relying on museum and library collections, equipment, video and film, testimonials and Web sites.

B. Analyze the physical concepts behind hitting, pitching and fielding as they impact the way baseball is played, including tools that are used and how scientific variables affect choices and approaches to the game.

C. Understand the vocabulary and several concepts of physics related to fundamentals of scientific inquiry that transport learning beyond the baseball diamond.

III. Preparing the Students
A. Background
Baseball fans, and even those who do not necessarily enjoy the game, may be surprised to learn how science directly influences a batter's ability to hit the home run, a pitcher's talent for throwing a curve ball, or a fielder's spectacular diving catch. While professional athletes do not necessarily understand the physics of their sport, the principles and concepts of science can enhance their performance when studied and applied to the execution of fundamental skills on the diamond. All-Star players, such as Derek Jeter, Roger Clemens and Ozzie Smith, may intuitively understand and apply physics in using gravity, effort force, speed, momentum and velocity to their advantage. Even those players who do not comprehend the theories of science and their relevance to the game are demonstrating physics and incorporating mathematics, often unaware they are doing so. Grasping how to use these variables to one's benefit can mean the difference between a Hall of Fame career and a brief stay in the major leagues. Standing waves, center of mass, the effort force on a lever, impulse, friction, aerodynamics, and projectile and linear motion are all intricate to strategy in the dugout and rivalries on the field as teams compete in using physics to their athletic advantage.

B. Vocabulary
Acceleration
Aerodynamics
Air resistance
Angle
Center of mass
Collision
Conservation of Energy
Density
Distance
Energy
Effort force
Force
Friction
Fulcrum
Gravity
Impulse
Lever
Linear motion
Mass
Momentum
Newton's Laws of Motion
Node of standing wave
Pressure
Projectile motion
Rebound force
Speed
Sweet spot
Velocity
Vibration
Wave
Work

C. Suggested Pre-Program Activities
1) Have two students hold a Slinky toy between them. Stretching the Slinky on the ground across several feet, have one student swing it back and forth, side to side. This demonstrates the highs and lows of a standing wave caused by the vibrating movements.

2) Discuss types of levers used in daily life. List examples of first-, second- and third-class levers and the differences between them. Different types of levers can be illustrated by using a block of wood (a fulcrum), a ruler (a lever) and a weight to create resistance.

3) Find the center of mass or gravity of different objects by balancing them on a fulcrum. Ask students why they cannot stand themselves straight against a wall and bend over to touch their toes without moving their heels. Explain that this task is challenging because their center of mass is no longer over their feet, thus causing them to lose their balance.

4) After measuring the mass and volume of different objects, calculate and compare their density. These items might include cork, wood, metal, plastic, aluminum, etc.

5) Determine the amount of friction acting on a block of wood as it is pulled across different surfaces as measured by a force measure, such as a spring scale. The surfaces might include leather, a table, sandpaper, indoor/outdoor carpeting, grass, dirt, etc.

IV. Presentation If you are participating in a school visit or videoconference please do not review this section with your students. It will be taught as part of the presentation.
A. Opening
1) Show video footage or photographs of a player (or players) preparing for a turn at bat. This could include the sequence of him moving from the dugout to the batter's box, donning the batting helmet, selecting a bat, applying pine tar and swinging the bat with weights in the on-deck circle, advancing to the plate, and finally hitting the pitch for a home run. Additional segments could show the pitcher, the coaches, baserunners and other players each preparing for the player's at-bat.

2) Review the player's at-bat and discuss how equipment and other variables contributed to the hitter's success at the plate. Challenge the students to explain how this player hit a home run, while at the same time explaining why most hits are not home runs.

B. Lesson
1) Display a photograph of Mark McGwire hitting a pitch, showing the flexibility of his bat and the impact of the ball. Ask the students if they think his at-bat resulted in a home run. Explain his bat is bending because the waves of impact are causing the bat to vibrate, thus transferring less energy to the ball. Less energy translates into less distance and speed. Therefore, point out this at-bat did not likely result in a home run. In fact, his bat may have broken on this pitch.

2) Leading the students to focus on the player's bat as one aspect in his ability to stroke a homerun, have students find the sweet spot of a bat by using a rubber reflex hammer or a baseball. Using the hammer to move up the bat, waves will cause the bat to vibrate until the hammer strikes the sweet spot (the node of standing wave). At this point the student will feel very little vibration in the knob of the bat and the reflex hammer will bounce off the bat with greater force. Students should also be able to discern a different sound made by the reflex hammer at the "sweet spot".

3) Ask them to compare and contrast how a hitter like a McGwire might have performed differently if swinging an aluminum bat versus a wooden bat. Would his bat have broken? Would the ball have traveled farther? Does an aluminum bat have a different sweet spot or center of mass than a wooden bat? Repeat the sweet spot demonstration using the reflex hammer on an aluminum bat.

4) Demonstrate how to find the center of mass (or gravity) by positioning two fingers of each hand at either end of the bat, slowly moving them together until the bat balances perfectly on all four fingers. This activity may also be demonstrated using a simple fulcrum or another object for balancing.

5) Ask why an aluminum bat is not allowed in Major League Baseball. Briefly discuss the safety and impact of wood versus aluminum, illustrating the advantages an aluminum bat provides to the hitter. Have a conversation about standardization of equipment between modern-day baseball and previous eras.

6) Talk with students about another type of bat not allowed in baseball (i.e. a corked bat). Discuss why a corked bat has less mass, thus increasing bat speed and provides an unfair advantage to the hitter - even though research shows a corked bat does not provide an advantage in hitting the ball a greater distance. Compare the density between small blocks of wood and cork.

7) Show a cupped bat and briefly discuss the advantages it provides in terms of bat speed, such as less mass enabling a quicker swing. Review the regulations and previous debates that preceded the rule permitting a cupped bat in Major League Baseball. Cite the story of Hall of Famer Lou Brock who was one of the first players to use a cupped bat in the 1970s, causing a small controversy about whether or not it gave the hitter an unfair advantage.

8) Review how the properties of the bat, in conjunction with the player's athletic ability, better enable the application of force to propel the baseball. Compare the effort force of swinging of a baseball bat with other objects, such as a broom, a yardstick or a two-by-four - all of which are levers. Ask why ballplayers might move their hands (i.e. choke up) to increase control, reaction time, power and leverage depending on the situation and strategy. Correlate these actions to the physics principle of effort force on levers. Ask students to demonstrate how to choke up (or down) on the bat handle.

9) Having students hold a bat, ask them to slowly demonstrate how the knob of the bat becomes a fulcrum that influences leverage or effort force of the hands. Illustrate how a player makes choices based upon this principle, such as increasing force (i.e. gripping the bat at the end of the knob) to increase power and distance, or decreasing force (i.e. choking up) to increase control while sacrificing power and distance.

10) Having one student hold the bat at the end of the handle with one hand, ask another student to pull up on the bat, using the index finger and thumb, at different points to find the point where effort force is either easier (lighter) or more difficult (heavier) to apply. Ask the students to explain at what point it is easier to lift up on the bat. This activity illustrates the concept of a lever in exerting effort force.

11) Create scenarios that require students to make hitting choices based upon the concept of effort force. Ask a student to come to the front of the class to demonstrate one of the following:

a) The coach calls for a hit-and-run, requiring the batter to make contact with the ball and advance the runner(s);

b) The coach calls for the hitter to swing away with no outs, runners on every base and your team down by three runs;

c) The coach calls for a bunt, requiring the batter to decrease the force or deaden the impact of the ball to move the runner over.

12) Using the example of one bunting technique, demonstrate how pulling the bat back and increasing its contact time with the baseball lessens the rebound force and velocity of the hit. One way to illustrate this is to place a glove on the end of the bat to, in effect, catch the baseball, thus changing its momentum and direction. This is also an example of impulse (force x time) as a physics principle.

13) Using a bat and ball, pair the students to have one player roll a ball across the floor while the other player lessens its momentum by softly pulling back on the bat. This illustrates the concepts of angle and impulse as they apply to bunting. Compare and contrast the effects of pushing the bat against the ball to demonstrate the application of a greater force to increase momentum. Compare the bounciness of two baseballs if one of the balls is placed in a freezer one hour prior to the test. The students should discuss the force and momentum of the rebounding balls in the different situations.

14) Furthering the concept of impulse, show examples of major league players executing bunts in real-game situations. Compare this action to the skill of catching, also showing video or photographs of players making successful, spectacular fielding plays on ground balls or fly balls.

15) Provide a small brown paper lunch bag to each student, asking him or her to form his or her own handmade glove. Using these gloves, demonstrate the principle of spreading the force of impact by adding a layer of paper padding to the hand. Add a discussion about the purpose of catching with two hands to further lessen the ball's impact. In baseball, this is referred to as the "soft hands" approach.

16) Compare these crudely fashioned gloves with leather gloves worn by professional ball players. Discuss the differences, emphasizing the surface friction of paper versus the surface friction of leather. Ask why players at each position use different types of baseball gloves with surface areas of varying sizes.

17) What are other examples of when players wear gloves? Ask why hitters use batting gloves, pine tar or sandpaper on the handle of the bat to increase friction. Ask how the cleats or spikes worn by a player also provide friction. What scientific benefits do these elements provide to the hitter when facing a pitcher? Contrast those with benefits the pitcher might employ when facing the batter.

18) While talking about throwing and pitching, relate the concept of friction to the aerodynamics of a baseball in flight. Simply discuss the effects of gravity, air resistance and friction on the rotation of a baseball that is pitched, thrown or hit. Show a graphic that illustrates this principle. Ask what factors (i.e. the stitches on the baseball, how the ball leaves the bat, the air temperature, wind speed, etc.) cause a baseball to rise, spin, sink or curve. When is a baseball in flight an example of projectile motion (a home run or line drive hit by a player) and when is it an example of linear motion (a fastball from a pitcher or a ball thrown by a player)?

C. Conclusion
1) Return to the original sequence of the player progressing from the dugout to the batter's box, finishing with footage of the home run. Using still photos from the sequence, ask students to match each action with a principle of physics found in the discussion and vocabulary words for this lesson.

2) Conclude by again asking students to recap the different forces that affect whether a batted ball is a home run, a base hit, a ground out or a fly out. End the lesson by showing photographs or video highlights of various pitches, hits and fielding plays - culminating with a home run.

V. Enrichment and Assessment Activities
A. Using a toy that projects ping pong balls or rubber bands, graph the angle of launch versus the distance the projectile travels - being careful not to change the force on the object. Then change the force, keeping the angle the same to see the different effect.

B. Using the above activity, simulate a ballpark to determine the variables needed to achieve a home run.

C. Using a styrofoam or Wiffle ball, demonstrate the aerodynamics created when different spins are applied to the ball.

D. In an open area outdoors, allow students to toss eggs or water balloons to each other to demonstrate the effect of impulse on the object. This correlates to the "soft hands" approach when catching a baseball.

E. Drop different types of balls from the same height on the same surface to measure the elasticity or coefficient of restitution of balls made from different materials (i.e. a tennis ball, basketball, golf ball, baseball, ping-pong ball, soccer ball, etc.). Then change the surface variable while using the same ball to measure the elasticity or bounciness of the surface.

F. To demonstrate reaction time, have two students work together using a metric ruler. One student will hold the ruler with the 0 cm end between the other student's thumb and forefinger. This student will catch the ruler when it drops. Look where the ruler is caught. Look at the reaction times worksheet and read the reaction time for the distance on the ruler. Repeat the activity twice. Find the average of the reaction time trials to get the reaction time. Have the students switch places and repeat the same procedures to find the other person's reaction time. A variation of this activity is to have the student dropping the ruler say "ball" or "strike" as the ruler falls. The other student must catch the ruler if it is a strike or let it go if it is a ball.

VI. Additional Resources
A. Literature
Adair, Robert. The Physics of Baseball. Harper Collins, New York, 2002.

Bahill, A. T., and D. G. Baldwin, The rising fastball and the perceptual illusions of batters. In Biomedical Engineering Principles in Sports, ed. G. Hung and J. Pallis. Kluwer Academic, 2004.

Bahill, A.T., and T. LaRitz, Why can't batters keep their eyes on the ball? American Scientist 72:249-253.

Barr, George. Sports Science for Young People. Dover Press, 1991

Baldwin, D. G., and A.T. Bahill. A model of the bat's vertical sweetness gradient. In Proceedings of the 5th Conference of Engineering of Sport. Ed. M. Hubbard, R. D. Mehta and J.M. Pallis. International Sports Engineering Association. Sheffield, UK, 2004.

Froman, Robert. Baseball-istics: The Basic Physics of Baseball. Putnam, 1967.

Gutman, Dan. Carver, Tim. The Way Baseball works. Simon & Schuster, 1996.

Kindall, Jerry. Science of Coaching Baseball. Human Kinetics, 1991.

Klawans, Harold. Why Michael Couldn't Hit: and other Tales of Neurology of Sports. W.H. Freedman, 1996.

Gundersen, Erik. The Handy Physics Answer Book. Visible Ink Press, 1999.

Schrier, Eric W. Altman, William F. Newton at the Bat; The Science in Sports. Scribner, 1984.

Watts, Robert G. and T. A. Bahill. Keep Your Eye on the Ball: The Science & Folklore of Baseball .W. H. Freedman, 1990.

Watts, Robert G. and T. A. Bahill. Keep Your Eye on the Ball: Curve Balls, Knuckleballs and Fallacies of Baseball .W. H. Freedman, New York, 2000.

B. Web Links
baseballhalloffame.org
Official site of the National Baseball Hall of Fame and Museum

exploratorium.edu/baseball
The science of baseball

snap.com
Links to the physics of baseball

kettering.edu/~drussell/bats
The physics of the bat-ball collision

npl.uiuc.edu/~a-nathan/pob
The Physics of Baseball

pbs.org/saf/1206/resources/
PBS-Scientific Frontiers: On the Ball: Baseball Technology

m-5.eng.uml.edu/umlbrc/
UMass-Lowell Baseball Research Center Home Page

http:// sie.arizona. edu/sysengr/baseball/2Seam-4Seam
Bahill, A.T. Baseball video

C. Multi-Media Gallery
1) Excerpts from Fastballs, Flips and Physics: Science on the Sandlot Electronic Field Trip video

2) Recommended Movies for In-Class Viewing
a) Batting with Ted Williams" (plus "The Science of Hitting). These two instructional films are combined in one 53-minute color video. "Batting with Ted Williams" was filmed in 1966 as Williams demonstrates the fundamentals of good hitting. The second film, based on his book, "The Science of Hitting," was produced in1972. Color. 53 minutes.

b) Mom, Can You Teach Me How To Hit? Video & DVD. 2003, Color. 75 minutes.

3) Photographs
a) Hank Bauer
b) Wade Boggs
c) Roger Clemens
d) Roger Clemens pitching sequence
e) Lenny Dykstra's cleats
f) Andres Galarraga
g) Benji Gil batting
h) Benji Gil fielding
i) Ken Griffey Jr.
j) Fred McGriff
k) Mark McGwire
l) Paul Molitor
m) Albert Pujols
n) Alex Rodriguez
o) Sammy Sosa
p) Bat selection
q) Bat-Ball Collision
r) Evolution of Gloves

VII. Relevant National Learning Standards
A. Science
1) Knows that the mass of a material remains constant whether it is together, in parts, or in a different state

2) Knows that substances can be classified by their physical and chemical properties (e.g., magnetism, conductivity, density, solubility, boiling and melting points)

3) Knows that materials may be composed of parts that are too small to be seen without magnification

4) Knows that heat is often produced as a byproduct when one form of energy is converted to another form (e.g., when machines and living organisms convert stored energy to motion)

5) Knows that energy is a property of many substances (e.g., heat energy is in the disorderly motion of molecules and in radiation; chemical energy is in the arrangement of atoms; mechanical energy is in moving bodies or in elastically distorted shapes; electrical energy is in the attraction or repulsion between charges)

6) Knows that all energy can be considered to be either kinetic energy (energy of motion), potential energy (depends on relative position), or energy contained by a field (electromagnetic waves)

7) Understands the law of conservation of energy (i.e., energy cannot be created or destroyed but only changed from one form to another)

8) Knows that vibrations (e.g., sounds, earthquakes) move at different speeds in different materials, have different wavelengths, and set up wave-like disturbances that spread away from the source

9) Knows that the earth's gravity pulls any object toward it without touching it

10) Understands general concepts related to gravitational force (e.g., every object exerts gravitational force on every other object; this force depends on the mass of the objects and their distance from one another; gravitational force is hard to detect unless at least one of the objects, such as the Earth, has a lot of mass)

11) Knows that an object's motion can be described and represented graphically according to its position, direction of motion, and speed

12) Understands effects of balanced and unbalanced forces on an object's motion (e.g., if more than one force acts on an object along a straight line, then the forces will reinforce or cancel one another, depending on their direction and magnitude; unbalanced forces such as friction will cause changes in the speed or direction on an object's motion)

13) Knows that an object that is not being subjected to a force will continue to move at a constant speed and in a straight line

14) Knows that when a force is applied to an object, the object either speeds up, slows down, or goes in a different direction

15) Knows the relationship between the strength of a force and its effect on an object (e.g., the greater the force, the greater the change in motion; the more massive the object, the smaller the effect of a given force)

16) Knows that good scientific explanations are based on evidence (observations) and scientific knowledge

17) Plans and conducts simple investigations (e.g., formulates a testable question, makes systematic observations, develops logical conclusions)

18) Uses appropriate tools and simple equipment (e.g., thermometers, magnifiers, microscopes, calculators, graduated cylinders) to gather scientific data and extend the senses

19) Knows that scientific explanations must meet certain criteria to be considered valid (e.g., they must be consistent with experimental and observational evidence about nature, make accurate predictions about systems being studied, be logical, respect the rules of evidence, be open to criticism, report methods and procedures, make a commitment to making knowledge public)

20) Understands how scientific knowledge changes and accumulates over time (e.g., all scientific knowledge is subject to change as new evidence becomes available; some scientific ideas are incomplete and opportunity exists in these areas for new advances; theories are continually tested, revised, and occasionally discarded)

21) Knows that from time to time, major shifts occur in the scientific view of how the world works, but usually the changes that take place in the body of scientific knowledge are small modifications of prior knowledge

22) Knows that there is no fixed procedure called "the scientific method," but that investigations involve systematic observations, carefully collected, relevant evidence, logical reasoning, and some imagination in developing hypotheses and explanations

23) Designs and conducts a scientific investigation (e.g., formulates hypotheses, designs and executes investigations, interprets data, synthesizes evidence into explanations, proposes alternative explanations for observations, critiques explanations and procedures)

24) Establishes relationships based on evidence and logical argument (e.g., provides causes for effects)

25) Knows that scientific inquiry includes evaluating results of scientific investigations, experiments, observations, theoretical and mathematical models, and explanations proposed by other scientists (e.g., reviewing experimental procedures, examining evidence, identifying faulty reasoning, identifying statements that go beyond the evidence, suggesting alternative explanations)

B. Mathematics
1) Uses a variety of strategies to understand problem situations (e.g., discussing with peers, stating problems in own words, modeling problems with diagrams or physical objects, identifying a pattern)

2) Uses explanations of the methods and reasoning behind the problem solution to determine reasonableness of and to verify results with respect to the original problem

3) Understands how to break a complex problem into simpler parts or use a similar problem type to solve a problem

4) Reads and interprets data in charts, tables, plots (e.g., stem-and-leaf, box-and-whiskers, scatter), and graphs (e.g., bar, circle, line)

5) Uses data and statistical measures for a variety of purposes (e.g., formulating hypotheses, making predictions, testing conjectures)

6) Understands different methods of curve-fitting (e.g., median-fit line, regression line) and various applications (e.g., making predictions)

7) Understands how the reader's bias, measurement error, and display distortion can affect the interpretation of data

8) Understands the defining properties of three-dimensional figures (e.g., a cube has edges with equal lengths, faces with equal areas and congruent shapes, right angle corners)

9) Understands the relationships between two- and three-dimensional representations of a figure (e.g., scale drawings, blueprints, planar cross sections)

10) Understands that mathematics has been helpful in practical ways for many centuries

11) Understands that mathematicians often represent real things using abstract ideas like numbers or lines; they then work with these abstractions to learn about the things they represent

12) Understands that mathematics is the study of any pattern or relationship, but natural science is the study of those patterns that are relevant to the observable world

13) Understands that mathematics provides a precise system to describe objects, events, and relationships and to construct logical arguments

14) Understands that mathematics often stimulates innovations in science and technology

15) Understands that mathematicians commonly operate by choosing an interesting set of rules and then playing according to those rules; the only limit to those rules is that they should not contradict each other

16) Adds, subtracts, multiplies, and divides whole numbers, fractions, decimals, integers, and rational numbers

17) Selects and uses appropriate computational methods (e.g., mental, paper and pencil, calculator, computer) for a given situation

18) Uses proportional reasoning to solve mathematical and real-world problems (e.g., involving equivalent fractions, equal ratios, constant rate of change, proportions, percents)

19) Understands how different algorithms work for arithmetic computations and operations

20) Understands the basic concept of rate as a measure (e.g., miles per gallon)

21) Selects and uses appropriate units and tools, depending on degree of accuracy required, to find measurements for real-world problems

22) Understands formulas for finding measures (e.g., area, volume, surface area)

C. Technology
1) Knows that scientific inquiry and technological design have similarities and differences (e.g., scientists propose explanations for questions about the natural world that are always tentative and evolving, and engineers propose solutions relating to human problems, needs, and aspirations; both science and technology depend on accurate scientific information and they cannot contravene scientific laws)

2) Knows that science cannot answer all questions and technology cannot solve all human problems or meet all human needs

3) Knows ways in which technology has influenced the course of history (e.g., revolutions in agriculture, manufacturing, sanitation, medicine, warfare, transportation, information processing, communication)

4) Uses appropriate tools, techniques, and quantitative measurements to implement proposed solutions

5) Knows that people have invented and used tools throughout history to solve problems and improve ways of doing things

6) Understands the relationships between elements (i.e., components, such as people or parts) in systems

D. Language Arts
1) Students conduct research on issues and interests by generating ideas and questions, and by posing problems. They gather, evaluate and synthesize data from a variety of sources (e.g., print and non-print texts, artifacts, people) to communicate their discoveries in ways that suit their purpose and audience.

2) Students use a variety of technological and information resources (e.g., libraries, databases, computer networks, video) to gather, research and synthesize information and to create and communicate knowledge.

3) Students use spoken, written, and visual language to accomplish their own purposes (e.g., for learning, enjoyment, persuasion and the exchange of information).

E. Thinking and Reasoning
1) Identifies the values underlying the alternatives that are considered and the criteria that will be used to make a selection among the alternatives

2) Predicts the consequences of selecting each alternative

3) Makes decisions based on the data obtained and the criteria identified

4) Verifies results of experiments

F. Historical Understanding
1) Knows how to construct and interpret multiple tier time lines (e.g., a time line that contains important social, economic, and political developments …)

2) Understands patterns of change and continuity in the historical succession of related events

3) Knows how to periodize events of the nation into broadly defined eras

4) Understands historical continuity and change related to a particular development or theme

5) Analyzes the values held by specific people who influenced history and the role their values played in influencing history

6) Analyzes the influences specific ideas and beliefs had on a period of history and specifies how events might have been different in the absence of those ideas and beliefs

7) Analyzes the effects that specific "chance events" had on history and specifies how things might have been different in the absence of those events

8) Analyzes the effects specific decisions had on history and studies how things might have been different in the absence of those decisions

9) Understands that the consequences of human intentions are influenced by the means of carrying them out

10) Understands that change and continuity are equally probable and natural

11) Analyzes how specific historical events would be interpreted differently based on newly uncovered records and/or information

12) Understands how the past affects our private lives and society in general

13) Knows how to perceive past events with historical empathy

14) Knows how to evaluate the credibility and authenticity of historical sources

15) Evaluates the validity and credibility of different historical interpretations

VIII. Planning a Videoconference
A) Videoconference Checklist (PDF)

B) Teachers: You will need the following items for use during the videoconference.
1) You will need one wooden bat, one aluminum bat, and one baseball for each pair of students:

a) Wooden baseball bats

b) Aluminum baseball bats

c) Baseballs

2) One paper bag (lunch size) for each student