Transcript Fourth Grade Super Scientists!

Fourth Grade Super Scientists!
Welcome, fellow scientists!
We’ve spent the year investigating all sorts of
scientific topics, from weather to the solar
system, light and sound, force and motion,
simple machines, ecosystems, and animal
adaptations. It has been quite an exciting
adventure! I’m proud of all of your
discoveries! Let’s take a trip down memory
lane to review all of the fabulous information
we have learned! Come along with me…I’ll be
your guide!
Weather and the Water Cycle
We began our year right here
on planet Earth with a study of
all things weather-related! We
became expert meteorologists!
Let’s see what we learned!
Forms of Water
• There are 3 forms of water: solid,
gas, and liquid.
• The solid form of water is called
“ice.”
• Water in the form of a gas is called
“water vapor.”
• The liquid form of water is
called…water! 
Boiling and Freezing Points
• Water can change from one form
to another through the processes
of boiling, freezing, and melting.
• The freezing point of water is 32°
Fahrenheit, or 0° Celsius.
• The boiling point of water is 212°
Fahrenheit, or 100° Celsius.
The Water Cycle
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The water cycle is the continuous movement of water between Earth’s surface and the air, changing from liquid to
gas to solid.
Evaporation is when water is heated and changes from a liquid to a gas (water vapor).
Condensation is when water vapor cools and condenses back into liquid form. Clouds are made of condensation.
Condensation also forms on surfaces such as glass.
Precipitation is when water returns to the earth as rain, snow, sleet, or hail.
Types of Clouds
• Clouds form when water vapor rises,
cools, and condenses into water
droplets.
• The droplets join together to form
clouds.
• Cirrus clouds are high, wispy clouds and
are usually made of ice crystals.
• Cumulus clouds are puffy, flat-bottomed,
fair-weather clouds.
• Stratus clouds are low and gray and
blanket the sky.
• Cumulonimbus clouds are very tall and
dark. They bring thunderstorms.
Forms of Precipitation
• There are four types of precipitation:
rain, snow, sleet, and hail.
• Rain is the only form of liquid
precipitation.
• Snow occurs when water vapor turns
directly into ice crystals.
• Sleet occurs when raindrops fall
through layers of cold air and freeze.
• Hail is a layered ball of ice.
Weather Instruments
thermometer
wind vane
anemometer
rain gauge
barometer
• Thermometer – measures
temperature
• Wind vane – measures wind
direction
• Anemometer – measures wind
speed
• Rain gauge – measures how
much rain has fallen
• Barometer – measures air
pressure
“WHAT” is the Weather?
• All weather is made of 4
ingredients:
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Wind (moving air)
Humidity (moisture in the air)
Air Pressure
Temperature
Cold and Warm Fronts
Warm Front
Cold Front
• A front is a boundary between
air masses with different
temperatures.
• A warm front usually brings rain
and warmer temperatures.
• A cold front often brings violent
weather followed by colder
temperatures.
Predicting the Weather
• Meteorologists (weather
scientists) use weather
instruments to study the four
parts of the weather (wind,
humidity, air pressure, and
temperature.)
• They make a weather forecast
(hypothesis) based on the data
they collect.
Weather vs. Climate
• Weather is the daily condition of the
atmosphere in a place. Ex.: There is a
30% chance of rain for Snellville on
Thursday.
• Climate is the average weather in a
certain place over a long period of
time. Ex.: The desert has extreme
temperatures and little rain.
• Climate DOES NOT change from day
to day; weather does!
The Solar System and Beyond!
After our study of Earth’s
weather, we blasted off on
a journey of the solar
system….and beyond! We
became expert
astronomers!
What Makes Day and Night?
• We have day and night because
the Earth rotates on its axis.
• When our side of the Earth is
facing the Sun, we have day.
• When we are facing away from
the Sun, we have night.
Rotation and Revolution
• It takes the Earth 24 hours to
rotate once on its axis.
• It takes the Earth 365 days (one
year) to revolve around the Sun
one time.
• All of the planets in our solar
system rotate and revolve.
Rotation
Revolution
The Phases of the Moon
• The moon orbits around the
Earth. Because of this, the shape
of the moon appears to change
over the course of a month.
• There are about 2 weeks
between any 2 opposite phases
of the moon (such as new moon
and full moon).
Soaring Through Our Solar System
• Our solar system includes all of
the objects that orbit around
our Sun.
• There are 8 “official” planets
and several “dwarf” planets (like
Pluto)!
• The Sun is the ONLY star in our
solar system!
The Family of the Sun
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Mercury – closest to the Sun
Venus – Earth’s “twin”
Earth – Home sweet home!
Mars – the “red planet”
Jupiter – largest planet
Saturn – pretty rings!
Uranus – spins on its side
Neptune – windy blue planet
Pluto – now a dwarf planet!
Thanks, Mom! (A way to remember the order of the
planets!)
My (Mercury)
Very (Venus)
Educated (Earth)
Mother (Mars)
Just (Jupiter)
Served (Saturn)
Us (Uranus)
Nachos! (Neptune)
A couple more things about the planets!
• The inner planets (Mercury, Venus,
Earth, and Mars) are all rocky and
are much smaller than the outer
planets.
• The outer planets (Jupiter, Saturn,
Uranus, and Neptune) are HUGE
gas giants!
Twinkle, Twinkle, Little Star?
• Stars are balls of burning gases.
• The Sun is a medium-sized star.
• Stars’ temperatures vary based on
their colors.
• Blue stars are the hottest; red stars
are the “coolest.”
• Stars stay in one place in space.
Cool Constellations!
• Constellations are groups of stars
that seem to form a picture.
• There are 88 official constellations.
• We see different constellations in
different seasons because the
Earth revolves around the Sun.
Each season, we see a different
part of the night sky.
Stars vs. Planets
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Stars
Balls of burning gases
Stay in one place
Make their own light
Can be the center of a solar
system
Can be different colors
Have different temperatures
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Planets
Can be solid rock or made of gas
Revolve around a star
Travel in an orbit
Reflect light from the Sun
Can be different colors
Have different temperatures
Space Technology
• Astronomers use many tools to
study space.
• Some forms of space
technology include:
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Telescopes
Satellites
Space probes
Spacecraft (Apollo missions,
space shuttle)
– The International Space Station
The Reason for Seasons!
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We have seasons because the earth is tilted on its axis.
The hemisphere that is tilted toward the Sun is having summer.
The hemisphere that is tilted away from the Sun is having winter.
Fall and spring occur when the hemispheres are receiving fairly equal amounts of sunlight.
You Light Up My Life!
After returning to Earth, we
continued our explorations by
learning about the concepts of light
and sound! Come with me and I’ll
illuminate you about what we
learned! Sounds like fun, doesn’t it?
How Does Light Travel?
• Light travels at a speed of
186,000 miles per second!
• Light travels in straight lines
called rays.
Reflection – Mirror, Mirror, On the Wall
• Reflection occurs when light
hits an object and bounces off.
• Shiny, smooth surfaces cause
the most reflection.
• The law of reflection says that
the incoming and outgoing
angles of light must be equal.
Refraction – Break it Up!
• Refraction occurs when lights
bends or breaks as it goes
through a transparent object.
• When a prism is used to refract
light, it creates the visible
spectrum (a rainbow!).
So who is this ROY G. BIV?
• ROY G. BIV is a way to
remember the order of the
colors in the visible spectrum.
Red
Orange
Yellow
Green
Blue
Indigo
Violet
Absorption
• Different objects absorb
different amounts of light.
• Dark colors absorb light; light
colors reflect light.
• The colors we see are the colors
that are being reflected off an
object; all of the other colors are
being absorbed.
Transparent, Translucent, and Opaque
• Transparent objects allow ALL
light to pass through (ex.: clear
glass)
• Translucent objects allow SOME
light to pass through (ex.: wax
paper)
• Opaque objects allow NO light to
pass through (ex.: black
posterboard)
Lenses
• Lenses change how objects
appear by refracting light.
• Convex lenses bulge out in the
middle. They make objects
appear larger (ex: magnifying
glass).
• Concave lenses “cave in” in the
middle. They make things
appear smaller and sharper.
Sound – Good Vibrations!
• ALL sound is caused by vibrations! When an object vibrates, it causes the
air around it to vibrate. The vibrations travel to our ears in the form of
sound waves.
Frequency and Pitch
• Frequency (how often sound waves vibrate) determines the pitch, or highness or lowness,
of sound.
• High frequency = Fast vibration = High pitch
• Low frequency = Slow vibration = Low pitch
• When you tighten the strings of a guitar, the pitch gets higher because the frequency
increases.
• Large objects (like tubas) usually have lower pitches; small objects (like flutes) usually
have higher pitches.
Amplitude, Intensity, and Volume
• Amplitude and intensity have to do with the amount of energy in a sound
wave.
• Amplitude and intensity determine the volume (loudness or softness) of a
sound.
• High amplitude = loud; Low amplitude = soft
• Amplitude is measured in decibels.
How Does Sound Travel?
• Sound travels in waves by passing from one molecule to another.
• Sound travels fastest through solid materials because the molecules in a
solid are very close together.
• Sound travels slower through liquids and slowest through air (because air
molecules are much farther apart).
Force and Motion
After experimenting with light
and sound, we moved into the
topics of force, motion, and
simple machines!
What is a force?
• A force is a push or a pull!
• Gravity and friction are types of
forces.
• We have to apply a force to an
object if we want that object to
move.
• The greater the force, the greater
the movement!
What is work?
• Work occurs when a force is
applied, causing an object to
MOVE!
• Work ONLY occurs if something
is moved!
Gravity & Friction
• Gravity is a force that pulls all
objects toward Earth’s surface.
• Friction is an opposing force
that slows or stops movement.
• Rough surfaces create more
friction; smooth surfaces create
less friction.
Simple Machines
• Machines make work easier by
changing the direction of a
force.
• Most machines are made of a
combination of six simple
machines: wheel & axle, levers,
inclined planes, wedges,
pulleys, and screws.
Wheels & Axles, Gears, and Pulleys
• Wheels and axles make things
easier to move.
• Gears are “wheels with teeth.”
• A pulley is a grooved wheel
with a rope moving around it.
• Pulleys are used for lifting
heavy objects.
Inclined Planes and Screws
• An inclined plane is a slanted surface
(such as a ramp) which is used to
move things from a high place to a
low place or from a low place to a
high place.
• A screw is actually an inclined plane
wrapped in a spiral.
• Screws can raise or lower things, or
they can hold things together.
Wedges and Levers
• A wedge has an edge that is used
to split things apart or to cut things
(ex: a knife or a saw).
• A lever is a bar that rests on a
turning point called a fulcrum.
• Levers make it easier to move
loads.
• It is easier to move a load when
the FULCRUM IS CLOSE TO THE
LOAD.
The World of Living Things!
When we finished our “work” with
force and motion, we began an
exploration of ecosystems, biomes,
food chains and webs, and the
roles of living things! We learned
that everything is connected in the
“circle of life!”
Ecosystems & Biomes
Some of the major biomes include:
•Tundra
•Taiga
•Temperate forest
•Tropical rainforest
•Desert
•Grasslands
•Freshwater
•Salt water
• An ecosystem is the interaction of
living and nonliving things in a
certain area.
• A community is the living part of
an ecosystem.
• A population is a group of one
type of organisms.
• A habitat is where a certain
population lives.
• Different ecosystems are known as
biomes.
Producers, Consumers, & Decomposers
• The living things in an ecosystem have
different roles.
• Producers (PLANTS) are organisms that
make their own food using energy from the
Sun.
• Consumers are organisms that must get their
food from producers or from other
consumers.
• Decomposers are organisms that break down
living and dead matter. The decomposed
matter becomes part of the soil and provides
nutrients that enable new plants to grow.
Some examples of decomposers are
mushrooms, bacteria, and earthworms.
Herbivores, Carnivores, & Omnivores
A cow is an herbivore.
• There are three types of
consumers.
• Herbivores eat ONLY plants.
• Carnivores eat ONLY animals.
• Omnivores eat both plants AND
animals.
Many humans are omnivores.
A lion is a carnivore.
Food Chains and Food Webs
• Food chains show how energy
is passed from the Sun to
producers, consumers, and
decomposers.
• Food chains often overlap if
they include the same
organisms. When this happens,
it forms a food web.
Here Comes the Sun!
• The sun is the source of
energy for ALL food chains,
because all producers make
their own food using energy
from the sun.
It’s All Connected!
• Everything in our world is
connected! A change to one part
food web causes changes
throughout the rest of the web.
• For example, if plants become
scarce, it affects not only the planteaters, but also the animals that
eat plant-eaters.
Scarcity and Overpopulation
• Scarcity is when there is not
enough of a particular resource or
organism.
• Overpopulation is when there are
too many of a certain type of
organism.
• Both scarcity and overpopulation
can cause upset the balance of an
ecosystem.
Amazing Animal Adaptations!
After learning about how
everything is connected in the
circle of life, we learned about
some of the amazing adaptations
that enable animals to survive!
What is an adaptation?
• An adaptation is a certain body
feature or behavior that allows
an animal to survive in its
environment.
• Some adaptations include:
camouflage, hibernation,
protective covering, migration,
chemical defense, and many
more!
Camouflage and Mimicry
• Camouflage is when and animal
blends in with its environment
as a way of hiding from
predators
• Mimicry is when an animal has
characteristics similar to
another animal or plant
Hibernation & Migration
• Hibernation is a very deep sleep
to help an animal survive during
cold winter months.
• Migration is when animals
move from place to place to find
resources or to find a better
climate during the winter.
Protection & Fright
• Many animals have protective
coverings or coloring to warn
predators to stay away.
• Some animals frighten
predators away by appearing
larger than they are or by
making startling sounds.
Causes of Extinction
• In spite of their amazing ability to
adapt and survive, many animals
become extinct due to being
overhunted by humans.
• Other animals become extinct when
their habitats are destroyed, often by
humans.
• Many countries have made laws to
protect endangered animals so that
they won’t become extinct.
Science Safety Tips!
Wow! Science is so much fun!
However, it’s important to remember
these tips:
• Follow all instructions carefully!
• Use safety goggles when
necessary.
• Wear closed-toe shoes when
performing experiments.
• Never taste an unknown
substance!!
Keep on Investigating!
Well, that brings us to the end of
our trip down memory lane! I hope
you have learned a lot about
science this year! But most of all, I
hope that you will keep on
investigating so that you can
become a super scientist!
Your friend,