activity page will offer:
An introduction to how the brain infers the position of
a moving target.
hands-on activity in which a student uses a "look-ahead"
window to target a moving object.
opportunity to explore how variables affect the success
of targeting of a moving object.
- Scrap cardboard (for supports)
- Large cardboard rectangle (approximately 2 feet by 3 feet)
- Pencil (without point)
- Cardboard tube (toilet paper roll)
this activity, you will assemble an apparatus that will be
used to explore how you aim and successfully strike a moving
target. A moving marble will be exposed for a short time before
it disappears beneath a cardboard canopy. During the time
you observe the marble, your brain will analyze the movement
of the marble and use that information to infer its trajectory.
Using this "best guess" about the path of the marble, you
are ready to strike the marble as it emerges from the canopy.
- Working in teams of two, assemble four supports of scrap
cardboard. Each of the four supports should be about the
size of a child's wooden playing block. Use tape to secure
the shape of each stack.
- Obtain a rectangular section of cardboard (the larger,
the better). This "canopy" can be cut from the side of a
- Use tape to secure a support stack to each corner of the
rectangle. The rectangle should be lifted several inches
from the table's surface. Make sure that the rectangle does
not sag in its center. If it does droop, you may need a
sturdier section of cardboard or a smaller supported area.
- A pitcher is positioned at one end of the rectangle.
A batter is positioned at the opposite end.
SEE DIAGRAM BELOW
- The pitcher positions the cardboard tube so that a marble
will roll through the tube and travel beneath the cardboard
canopy. The tube should be positioned about six inches in
front of the edge of the canopy.
- At the batter's end, a section of tape is positioned on
the desktop that is parallel to the edge of the cardboard
rectangle. The tape should be set about an inch from the
edge of the cardboard. This line defines the back limit
of the batter's box--the hitting window.
- The batter holds a pencil "bat" and can only hit the marble
as it passes through this strike zone. Once the marble rolls
beyond the hitting window it can no longer be hit.
- Once the batter and pitcher become familiar with their
tasks, it's time to explore the targeting zone. How might
the speed of the moving marble affect accuracy? To find
out vary the inclination of the cardboard tube.
- Develop a strategy that would examine how looking at the
marble before it rolls beneath the canopy affects the success
of hitting the marble. How will doubling the distance between
the release of the marble and the time that it passes under
the canopy affect targeting? Is there a critical distance
over which the movement of the marble must be observed?
- What was the purpose of the taped rear limit to the batter's
- How would a longer targeting zone affect the accuracy
of hitting the moving marble? Make a prediction. Then, carry
out an experiment that will test your prediction.
- How did different inclination angles of the tube affect
the movement of the marble?
- How did different velocities affect the results?
- Did extending the targeting window affect the targeting
A Penny for Your Thoughts
the marble was replaced by a wobbling, rolling coin. Would
this exchange produce different results? Does a coin require
a longer observation window for successful targeting? Why
or why not? Think about it. Then, design a strategy that would
test the difference in successfully targeting the marble and
Do you bowl? If so, describe the moments prior to releasing
the ball onto the alley. What thoughts are going through your
head? Where are you looking? What are you thinking? Do you
need to concentrate? If so, what factors are you thinking
about before releasing the ball? Think about it. Does your
planned release change as you are in the process of throwing
the ball or do you get "locked" into this action while focusing
on your target?
Have you ever juggled scarves? If not, why not give it a try?
Unlike balls, scarves do not fall quickly when released. Instead,
their wide surface reacts with air molecules. This slows their
descent so that the scarves are more easily snatched during
their fall. Once you learn this juggling technique, have another
student observe your eye movements as you try to keep the
scarves aloft. Exchange positions and observe the eye movements
of your partner.
With your instructor's approval, develop a strategy for inquiry
that explores the targeting and movement processes associated
with basketball free throws. Does the amount of time targeting
the rim prior to the shot affect the accuracy? Will a lag
time between targeting and shooting affect accuracy? Are there
differences in the way males and females depend upon this
Dead Straight for Dead Aim
site presents an overview of targeting with specific reference
to improving golf skills.
Aids: The Dots and Arrows
This site presents a guide to using visual aids to help target
more Web links on this topic - visit our Resources
activities in this guide were contributed by Michael DiSpezio,
a Massachusetts-based science writer and author of "Critical
Thinking Puzzles" and "Awesome Experiments in Light & Sound"
(Sterling Publishing Co., NY).
Academic Advisors for this Guide:
Corrine Lowen, Science Department, Wayland Public Schools,
Suzanne Panico, Science Teacher Mentor, Cambridge Public Schools,
Anne E. Jones, Science Department, Wayland Middle School,