Selected activities suggested for grades 3 - 6 at schools hosting a

Sound and Waves Presentation.

Each activity is referenced to appropriate grade according to the Idaho State Board of Education.  Relevant chapters in the Houghton Mifflin Science "Discovery Works" series are also referenced.  HM 4D2.1 refers to Investigation 1 in Chapter 2, Unit D from the fourth grade text.  HM 2B6 refers to Lesson 6 in Unit B from the second grade text. 

SOUND AND VIBRATIONS WITH A COFFEE CAN DRUM
Principle: Sound, Vibrations
Grade: 2
HM 2B6, 5F3.1
    Remove the top and bottom from a large coffee can, or some other large, rigid cylinder.  Stretch plastic wrap tightly over one end and secure with a rubber band.  Duct tape the coffee can "drum" to a table top with the open end near a table edge.  Use clay to secure a flashlight or diode laser pointer to the table top so that a light beam strikes the plastic wrap and reflects onto a wall.  Turn the lights down so that the reflected beam spot is very clear.  Play amplified music, or speak, or sing loudly  into the coffee can drum.  You can increase the effect of your voice by speaking through a cone made of paper or a plastic cup with the bottom cut out.  The sound, which is a vibration of the air, will in turn vibrate the plastic wrap.  This vibration can be seen in the movement of the reflected beam spot.  Have one or two students place a finger or two on the plastic wrap to feel the vibrations.  The idea here is for your students to connect vibrations with sound.


SOUND AND STRING VIBRATIONS
Principle: Sound, Vibrations
Grades: 2, 5
HM 2B6, 5F3.1, 5F3.2, 5F3.3
    Cup your hands over your ears and have a partner loop 2' or 3' of multi-ply yarn around your head and over your hands.  Have your partner pluck the string and listen to the sound.  This activity will help students associate sound with vibrations.  Experiment with the tension, where the string is plucked, and how you cup your hands over your ears.  You can also change the weight of the string by unraveling one or more ply.  Try it with different strings.  Instead of cupping your hands, stick your fingers into your ears while holding the string.  Try tying a large metal spoon, ladle, or anything metallic to the end of the string and have someone tap it with something else metal.

A classic small group activity is to have students make string-and-cup phones.  Use large plastic cups, the more cone shaped the better.  Cut, poke, or drill a small hole in the center of the bottom of two cups, just a little bit larger that the diameter of the string you have chosen.  Poke one end of a long string up through the bottom of a cup and tie a large granny knot near the end, so the knot is inside the cup and the string hangs down below.  Repeat this for the other cup and the other end of the string.  If you speak loudly into one cup while someone holds the other cup to their ear with the string tight, they can hear what you say because the sound you make vibrates your cup which vibrates the string which vibrates the other cup almost the way your cup vibrated, so the air in the other cup carries sound which can be recognized as a voice.  This is best done through a partially closed door, curtain, or window so the sound one student makes through the air is not as noticeable to the student on the other end of the string-and-cup phone.  Experiment with different thicknesses and types of string.



SODA STRAW WAVE MACHINE
Principle: Sound, Vibrations, Waves
Grades: 2, 5
HM 2B6, 5F3.2, 5F3.3
    Take a couple of dozen soda straws and clip a paperclip to each end of every straw.  Measure out a little more than 2' of sticky tape, and stick a straw every inch or so with the tape in the middle of each straw.  Stick a second identical length of tape over the top of the straws to cover the sticky part of the first tape.  Hang the straw strip from a desk or table, pull it taunt, and give one of the straws at the top or the bottom a tap to start a transverse wave.  Increasing the tension will increase the speed of the wave, and increasing the density (by adding more paperclips) will decrease the speed of the wave.  Although sound is a longitudinal wave, best represented by compression waves in slinkys, the soda straw waves can be used to illustrate many of the properties of sound waves.

       
FILM CAN CRUMHORN
Principle: Sound, Vibrations, Resonance
Grades: 2, 5
HM 2B6, 2B7, 5F3.1, 5F3.2, 5F3.3
    I picked this gem up from Paul Doherty of the Exploratorium.  Drill a 13/16 inch hole in the bottom and in the lid of a 35 mm film can.  Also drill a ½ inch hole in the side of the film can.  Cut a 2-inch square out of a plastic garbage bag.  Spread the plastic square tight over the top of the film can to form a membrane, and seal it with the lid.  Push a ½ inch PVC schedule 40 pipe into the hole in the bottom of the film can until it just barely touches the plastic membrane.  Blow through the ½ hole and adjust the pipe until the horn honks.  The plastic pipe could be any length, but certain lengths sound better. You may wish to try different lengths.  Although the Film-can Crumhorn plays only one note, several Crumhorns of different lengths may play songs.  Pipe lengths are also listed in the following table, with corresponding notes.

Notes for ½ Inch Schedule 40 PCV Pipe
Note
Length (cm)
Frequency (Hz)
F
G
A
B flat
C
D
E
F
A
B flat
C
D
E
F
23.6
21.0
18.75
17.5
15.8
14.0
12.5
11.8
9.4
8.8
7.9
7.0
6.25
5.9
349
392
440
446
523
587
659
698
748
892
1046
1174
1318
1397
The above table was obtained from Bill Reitz and Gene Easter of the Ohio OPPS Team.

BOOMWHACKERS
Principle: Sound, Vibrations, Resonance
Grades: 2, 5
HM 2B6, 2B7, 5F3.1, 5F3.2, 5F3.3
    If a golf tube is whacked on a hard surface, such as your head, resonant vibrations will be set up in the tube.  Longer tubes will resonate with longer wavelengths, or lower pitch, and shorter tubes will resonate with shorter wavelengths, or higher pitch.  With both ends of the tube open, the length of the tube is ½ of a wavelength.  If one end of the tube is closed, the length of the tube is ¼ of a wavelength.  Sobe drink lids work great for capping one end of a Wilson Golf tube.  A tube with one end closed will be exactly one octave lower in pitch than a tube with both ends open.  The following table lists tube lengths, notes, and frequencies for Wilson Golf tubes open at both ends.

Notes for Wilson Golf Tubes
Note
Length (cm)
Frequency (Hz)
C       
D       
E       
F       

A       
B      
C      
62.9
55.7
49.4
46.2
41.0   
36.5
31.9
30.2
261
294
330
349
392
440
446
523


SODA STRAW REED PIPE
Principle: Sound, Vibrations, Resonance
Grades: 2, 5
HM 2B6, 2B7, 5F3.1, 5F3.2, 5F3.3
    Cut two narrow "V's" out of opposite sides of a plastic soda straw at one end, with the "V's" about 5/8" long.  Mash the two halves of the cut end flat between your molars to form a double reed like that on an oboe or bassoon.  With practice you can blow through the straw with the reed in your mouth to make a buzzing note.  You can stick the straw whistle into a polled piece of paper to make a slide (or trombone) whistle, or cut pieces off of the end of the straw with scissors while playing.  In any case, the pitch will increase if the whistle is shortened, or decreased if the whistle is lengthened.
               

CO2 BALLOON SOUND LENS
Principle: Sound, Vibrations, Resonance
Grade: 5
HM 5F3.2
    Place several small chips of dry ice (carbon dioxide) in a 12" or larger balloon and tie it off at the bottom.  Try to choose the dry ice chips so that the balloon gets as big as possible without popping.  This will probably take several attempts, so plan ahead.  Sound travels slower through more dense materials, so it will move slower through the balloon.  It will act as a lens for sound, focusing sound just like a clear glass marble or other lens will for light, since light travels slower through glass than it does through air.  Hold the balloon near an ear and see if you can hear the difference.