Light and Sound

I use a student text book with some good ideas. Some things we do in fourth grade are:

light - flashlight and mirror experiments to see how light reflects, testing materials to determine whether they let light through (opaque, etc.), kaleidoscopes from film canisters and microscope slides

sound - make a simple tuned musical instrument with rubber bands (or could be more complex), getting everyone to hold a ruler over the desk edge a different length and then "playing" them in order to make a song (cool!!), using a tuning fork to show vibrations

When I taught eighth grade optics, we did other things that I can't recall TOO well, but I remember designing a floor plan for a funhouse with a cashier in the middle and say 10 arcade machines and you had to put mirrors in so that the cashier could see every exit and arcade machine. They made periscopes. Also we tested the speed of sound on a soccer field.

This is a neat unit! There are some good websites out there for optical illusions. Plus the students find colour blindness and vision problems (near/far sightedness) interesting.

Good luck!

One activity I've done with students is to take an empty xerox box and line the bottom with different boxes that create an ocean floor. The lid of the box is covered with a grid. Using a skinny dowel rod students measure the distance of the depth(sonar). They graph it and then using clay recreate the way they think the ocean floor appears according to the data. Have students create periscopes to view around a corner.

Hi Jennie,

I'm doing a unit on Light and Sound for 4th grade next month. We aren't getting into heat much. Here are some of the things that I'm doing for light:

*using prisms and a white sheet of paper to discover how white light breaks up into colors.(outside, & you need a sunny day) I'm trying to get one prism for each group of 4.

*shining light from a flashlight through different filters (colored cellophane in layers workds) onto colored construction paper to find out what colors it makes

*using rope to demonstrate a light wave's motion (energy waves are in our 4th grade state expectations, it's probably a little advanced for 3rd)

*learning translucent, transparent, and opaque using wax paper, plastic wrap, and aluminum foil

*experimenting with curved mirrors-- I have a little bendable one that came with a science kit to see how light reflects in different directions

*finding out uses for lenses -- I'm taking in a pair of glasses, a microscope, a picture of a telescope, a magnifying glass, a camera, and other things that use lenses for the kids to look at, look through, etc. We're not going into convex or concave, I'm leaving that for their middle school science teacher.

If you have a local teacher store, go ask the person there. I have a TON of books w/ really good stuff. I could spend months on this!

Check the directory on this site, and also www.askeric.org, for lesson plans.

Hope this helps! E-mail me if you'd like the titles of the books I have (I don't have them with me right now)

Lisa

Hi...I teach grade 4 too and we are learning about light right now...a couple of experiments that we did are:
... secret messages...have students write a message then using red, cover what they wrote...place a red acetate over the message and when you shine a light on it you can read the message
...put a quater inside a pan...students stand back until they can not see the quater...add water to the pan...the quater is now visible
...using green, blue and red acetates shine a light through each one on a white piece of paper...when you overlap them white light appears
...using the primary colours of light you can create the secondary colours.
Hope this helps!

One I've done with various age groups shows how light can be scattered as it hits particles such as pollution. Fill a large glass jar with water. Shine a bright flashlight through the water from one side. The light will appear white. Now add milk a few drops at a time and watch what happens to the light. You can look at it from the sides of the jar or straight on. The particles of milk separate the shorter blue and green light rays from the longer orange and red ones.

this is one that always fascinates my 6th graders. to illustrate that white light is indeed made up of all of the colors of the spectrum i have them make up color wheels. i have a w.s. for this, but it can easily be done without it. draw 2 circles, approx 4" in diameter and divide them into 6 equal sections. (like old fashioned toy with disk spun around strings...i don't know how else to explain it)

have students lightly color each section using red, orange, yellow, blue, green, and violet.

glue the pieces, color sides out, to a posterboard and poke 2 holes near the center.

thread string through the holes, making one large loop with the wheel in the center.

put index fingers into loops on either end of the string and twirl the wheel around until the string will double up on itself.

pull string outwards, then inwards, over and over, causing the wheel to spin quickly...this will appear white.

technically it will appear slightly yellow-ish. if they had put 7 sections instead of 6, one being indigo it would be white.

hope this helps.

Latitude 101
Here is a simple light experiment that has always worked . I talk a little about how the eye and a camera works. I usually put a diagram on the board of the light passing through the lense and focusing upside down on the back of the eye or the camera film (light sensitive plate on digital camera). I then pass out magnifying glasses and a sheet of paper. We focus the overhead classroom lights on the paper. The students enjoy this but the best is yet to come. We turn out the classroom light and move to the windows. This time when we focus the light we can see that the images are upside down.

When we studied light two years ago with some friends, we just got some light from the library and what we walked away with was what I call "the three B's:"

1. You can block it. Play with shadows. Use opaque things, and things like wire window screens.

2. You can bend it. Use a prism.

3. You can bounce it. Use a mirror and have the kids direct a flashlight beam, "bounced" by a mirror, on the clock, the doorknob, etc.

After the three b's have fun learning about the speed of light. It takes about 8 mins. and 20 seconds for light to travel from the sun to the earth. Don't tell how long it takes, but tell the students that you will start a timer when you say "go" and you want them to guess when the light that left the sun on the word "go" will hit the earth. Say go and 8.33 mins. later the timer goes off. Did they guess right?

Get those little light paddles and have kids "mix" light. Light mixes differently than pigments.

Kids like doing those sun-art papers. They are blue photosensitive papers you can get from some school supply places. You put objects on the papers and put them in the sun and the sun fades the exposed paper, leaving shadows of the objects. The paper is a bit pricey. You can do the same thing, with less dramatic results, using dark construction paper. Natural objects like ferns look really nice, but you can also use things like combs, keys, and paper clips. Do this on a sunny, windless day.

Or, make silhouettes of the students' profiles using a large bright light in a dark room.

Show the students a laser pen. Remind them not to fool around with lasers and never to point the at someone's eyes.

See if you can find refraction grating glasses. I think either Edmund Scientific or Home Science Tools sells them by the dozen. They cost around a dollar each, if I remember right, maybe a little less. They have paper frames and cheap refraction gratings as lenses. Look at different types of light (fluorescent, incandescent, candle light, a spot of light from a laser pen, neon signs at night) and see the different halos each makes. If you have some chemicals around (and a book on safety!) you can burn crystals of copper, etc. and see that the flame is a different color and produces a different refraction grating halo. If you get enough of these glasses, you can send a pair home to keep with each student. That would be fun.

Hope these ideas help.

Kelly

I have to teach that light travels in a straight line until it hits an object in which it is either absorbed, reflected or refracted. I show that light travels in a straight line by getting 4 different index cards and putting a hole in the middle of the 1st three. Then you line up the cards and shine a flashlight on the holes. The light should go though the wholes and hit the last card. Then we take one of the cards and move it so that the light will be absorbed. This is an investigation from my textbook.

The kids LOVE to see reflection. I normally take the kids to a bathroom that we can turn off all the lights and it has a mirror. I shine a flashlight into the mirror and have the kids find where the light BOUNCES (or reflects) onto the wall. Then we block the light (making shadows). For some reason they like to see the light bounce. It is like they get what reflection means.

To bounce off Azure's suggestion, a tuning fork can be tons of fun. My kids always enjoy me striking it, getting one of them to hold a full glass of water, and then sticking the tuning fork in to show that the sound waves travel (and splash!) in water very well. It is also fun to experiment with the tuning fork on the end of a plastic cup or the garbage can to show how a megaphone works.

I like to bring in a big kettle, cover the top tightly w/ aluminum foil and sprinkle salt on it. We then use different items, ie., banging a pot lid with a spoon, a volunteer screamer, a whistle, etc., and I have the children make that noise close to the salt to watch it "dance". This is an excellent visual to prove to them that sound waves may not be visible, but they are moving nonetheless.

Here are a few ideas:
Put rice on the speaker of a CD player or radio. They bounce all around.
The next activity is a lot of fun. I think I got it from AIMS. You draw a lion's head. Run off on oaktag. Cut out, and where the mouth is cut a circle the diameter of a styofoam cup. Put a string in the middle of the cup and leave about 8-10 inches.Tie the end to a paper clip so it doesn't slip out. Then put the cup into the hole. When you pull the string between your thumb and first finger it does sound like a "roar". I always try it before I put it in the lion and the kids can't hear it. But when it is in the lion they can hear the roar. When you put the string in the cup the string should hang down from the bottom of the cup. The paper clip should be inside the cup. I hope I explained this well enough.I just checked and it is from AIMS from the Primarily Physics book. Maybe you could find someone who has it and borrow the pattern. It has some great sound ideas in it.

Hello, I teach 4th grade, this is my first year.....when i student taught last year...my unit was on sound. These are some things i used.
I took them outside and sat them down for 10 minutes and just had them listen. Then bring them inside and let them listen. Then brainstorm on the board what they heard out and inside. You can do a KWL chart on sound to begin. You can find an alarm clock and put it inside a coffee can, a cardboard box, a plastic bag.....show them that sound travels through some objects. Make a paper cup telephone......describe the MAIN parts of the ear....second graders wont need all the parts. Take a ruler and place it at different areas hanging off the desk, then pull and let it go.....show them that because of the different lengths it makes a different sound. I hope this was helpful....im giving you these from my head since my unit is at school. Email me if you need to. ajcj98@att.net

Hold class outside. Using a clipboard, have the student write down every sound that they hear in fifteen minutes. Then go back into the classroom, form several small groups to make a master list on chart paper, then have the groups share with the class.

You could also assign small groups of students and have them write down only sounds they hear or know of that only animals make, humans make, machines make, etc. Or assign this as a homework activity: What sounds can you hear from your bedroom window?

Then, do a science lab about the ear drum and sound vibrations using a toilet paper tube, waxed paper and a rubber band, or put a broken rubber balloon on the tube and blow against a sunlit wall to see the vibrations. Use a slinky to demonstrate how sound travels. Do an experiemnt on how sound travels through different objects. Also, have students hold two fingers to each side of their next and feel the difference in vibration as they make different noises.

For fun, have one student do a mystery noise once everyday: everyone closes thier eyes while one student shakes a can of pennies, rolls marbles around in a can, shakes a can of spray paint, slurps a drink with a straw, crushes a can, etc. Have kids post sticky notes for guesses on the board. The person who guesses correctly get to bring in and do the next mystery sound.

Have fun!

You need: 1 metal clothes hanger (no plastic coating), two pieces of string about 2 to 3 feet long, pencil

Tie a loop at the end of each piece of string large enough for an index finger to fit in to

Tie the other end of each string to the bottom corners of the metal clothes hanger.

Put an index finger in each loop and suspend the clothes hanger above the floor (yes, the clothes hanger is now up-side-down)

Have a partner tap the clothes hanger once with a pencil. Note the sound.

With the loops still on the index fingers, put your fingers in your ears. The clothes hanger should still be suspended above the ground.

Have the partner tap the clothes hanger again. Note the difference in sound. I love the expression on the children's faces.

(the lesson? -- Sound travels thru solid objects very well!!!)