Why do we have Night?
Subject: Science - level: Elementary: 2nd grade
Preparation time: 5 mins.
Instructional teaching time: 25 mins.
Like an astrononmer, we are going to make a model of the sun and Earth to help explain why there is night. Models are also useful when something is happening too fast or too slowly for you to observe. We can't take a trip out into space to observe how the sun and Earth are moving. But you know that the sun in the source of light for day. With models, you can explore what the sun and Earth do to cause day and night.
Before beginning this science lesson you may want to read, "the Truth About the Moon", by Clayton Bess. Boston: Houghton Miffin Co. 1983. Have the students look and listen for all the answers to the character Sumu's questions regarding the moon. Ask the students what they might say to Sumu if he asked them about the moon. Later after studing this lesson and reading current facts about the moon, Earth and sun compare the information.
The study of the solar system is an essential topic in todays curriculum. Space travel, discoveries and experiments are comment talk on the news, Public television and radio. Todays students have the need to be informed thinkers with update vocabulary. This hands on activity will provide them with the oppurtunity to experience Earths rotations.
The purpose of this lesson is to provide the students with a fun, creative way to discover how the Earth moves.
This will help children understand why there is day and night. It can also create curiosity to further study the solar system and ecliopses!
A world Globe and a map of the USA
one flashlight per group of 4 students
3 toothpicks per student
box of raisens
one apple per student
two helpful class parents for supervision would be great!
box of knapkins
soap and water (sink)
1. To be able to locate the state where we live on the map of the USA.
2. To be able to locate the USA on the world globe.
3. To introduce basic vocabulary words: Earth, moon, sun, day, night, rotate, spin, challange word: eclipse.
4. To allow the student to observe then predict the outcome of the experiment.
5. To allow the student to gather and record data from the experiment.
6. To be able to apply information gathered and interpert data.
7. To be able to demonstrate the interperted data.
8. To draw pictures about the experiment.
9. To encourage further reading about the solar system.
PROCEDURE FOR THE EXPERIMENT:
1. Gather the students comfortabley around the display of the globe and map. Show them where the state the school/home is in. Mark this spot with a glued raisen.
2. Ask if any one can then find this state on the globe. Mark this spot with a removeable sticker. Discuss how the globe is our Earth. Explain how our Earth is rotating out in space.Ask the students to tell you about the moon.
3. Read the story, "The Truth about the Moon". Then a brief discussion. Write answers on a chart paper to save for later.
4. Divide the class into small groups by giving each child a star shape, or a moon shape or a sun shape or an Earth shape paper. This will help the children to quickley move into their correct group.
Distruipt the apples, toothpicks, rainsens, knapkins and flashlights to each of the four groups.
5. Demonstrate how to insert the toothpicks on the top and bottom of apples. Then show how to stick the raisen onto the side of the apple.Explain that the raisen represents the school/home just as the raisen did on the map of the USA.
6. Encourage helping parents to move about assisting the children with the toothpicks.
7. Demonstrate how the flashlight acts much like the sun does towards the Earth.
8. Demonstrate how when the light shines on one side of the apple this represents day.
9. Demonstrate how when the light is shining on one side the other side is dark representing night.
10. Rotate the apple so the raisen is in the light and then moves to the dark side. Ask students to recite out loud when they think the raisen is in day or night.
WHAT TO DO;
1. Stick the toothpick just far enough into the apple so you can use it as a handle.
2. With another toothpick stick one raisen onto the side of the apple.
The apple will be Earth in your model. The flasklight will be the sun in your model.
3. Hold the flashlight so that the light shines on one side of the apple. If the flashlight is the sun and the apple is the Earth, would it be day or night at the raisen? Is it dya or night on the other side of the apple?
4. With your group, think of two different ways to make day and night at the raisen. Record your ideas on your papers.
1. Imagine that you are standing on the raisen that is your school/home. How does the sun's position seem to change from where you are on the dot as you make night happen in each model?
2. Compare the ideas from your group to those of another group. Which one explains how we get night?
3. Discuss with your group what the moon does in space. Record your answers by drawing a picture on your papers.
4. Discuss what you think an eclipse is and what it looks like. Draw your answers on you paper.
5. Save your recordings in a science folder for later experiments.
6. Everyone wash your hands and your apples. Remove toothpicks and safely throw them iin trash. Spread out your knapkin and enjoy eating your apple and raisens.
1. Observe students as they particpate during the discussion time at the map/globe display. Did they maintain eye contact during discussion. Monitor the amount of student discussion. Did they show interest and energy for the topic?
2. Could the students easily identify the state on the map? The state on the globe?
3. How many students participated in discussion.
4. Could students retell the story of Summa?
5. Can the student recall specific vocabluary words?
6. Could student demonstrate the experiment within the grop?
7. Did the student discuss the experiment with other gropss?
8. Was artwork factual?
9. Was student able to make judgments on extention material?
10. Could retell each part of experiment?
11. Able to interopret ideas in own words?
12. Could recognize symbols, state shapes etc...
13. Able to problem solve within the group?
14. Could explain cause and effect of light in regards to day or night?
15. Uses lessons concepts to support their own opinions or views about eclipses?
Introduce the map of the solar system. Discuss where Earth is placed within the other planets.
Sing the song "There are Nine Lil' Planets "round the Sun",sung to the tune of "she'll be coming 'roung the mountain when she comes".
Count the planets and say their names, write their names on the chalkboard. Circle the first letter of each planet. 'M,V,E,M,J,S,U,S,P,'
An easy way to rember the placement of the planets: My Very Educated Mother Just Served Us Seven Pizzas.
Other great books to read are: "The Sun", by Seymour Simon, "My Place in Space", by Robin and Sally Hirst, and "The Orphan Boy" by Tololwa M. Mollel.
This lesson would fit nicely within the Changing of the seasons Science unit, Space unit, Mother Earth Science unit, Where we live, Social Studies unit. Counting rotations of the Earth could be reinforced during a Math unit. Create a small classroom library by allowing each student to display their folders for others to read and enjoy. Video tape this lesson and review the tape later in the Science Unit. Instead of drawing their pictures and ideas, the students may choose to record their answers on a tape recorder.
A field trip to a local Science Department. Contact a Local Forest ranger and ask her to explain what happens in the parks at night and day.