Working with a handmade oscilloscope
Summary
In this activity, students can make or use pre-made oscilloscopes and explore sound. They will be able to see how sound waves resonate through a beam of light.
CollapseLearning Goals
This lesson would be used when learning about sound and sound waves. Students should explore with different sounds going into the can to see the different patterns that are made with the beam of light. They should observe the different patterns, compare them, and discuss why they think the different patterns are being formed.
Context for Use
This lesson could be used for upper elementary levels and middle school levels. Students could each make their own oscilloscope or have one for a small group of students. Making the oscilloscope would take students about 20 minutes depending on the age group. And I would leave at least another 60 minutes for the lesson in addition to creating it depending on how much you are having students do with it. This lesson could be used in other settings easily. It could even be done with younger children as a whole group activity with exploration, discussion, and lecture.
Description and Teaching Materials
Students will first be building an oscilloscope. There are several different sets of directions for easy oscilloscopes to follow online. You can make the oscilloscope using a can, a balloon, a small mirror, a paint stir stick, some putty or play dough, and an inexpensive laser light. Glue a small piece of mirror onto a balloon that is stretched over a metal cylinder made from a can that is open on both sides. Aim the laser at the mirror and direct the reflected laser beam onto a wall (as far away as possible as this will enlarge the pattern of vibrations that is observed and make for a more striking experiment).
When they are finished building it, they should explore on their own to try and figure out what it is and how it works. Aside from giving them the building materials, I wouldn't give them any other directions until it is necessary.
After students have explored with the oscilloscope, I would have some whole group discussion to see where they are at and make sure all students are on the same page.
I would have previously gathered some noise makers (everything from instruments, toys, music, etc.) for the lesson. I would have students use a variety of the different noises and observe what kind of pattern comes from the beam. If it's possible for students to have access to a computer with speakers, they could also use a variety of music types. If students don't have access to computers with speakers attached, I would have a group demonstration so that they can see the different patterns that music makes. I would demonstrate a variety of types of music. Classical, jazz, and Broadway music make great patterns on the wall. I would also use music that they are interested in as long as it was appropriate.
I would have students document the different patterns that they saw, describe some of the differences. Discuss why they thought some of the patterns were made, etc. This is going to change depending on the different goals that you have for the lesson. There are also a few online demonstration videos you could view with the class after they have finished if you wanted to add more to the lesson or have some more whole group discussion as well.
In closing I would discuss how this relates to what students have been learning about sound and sound waves. This lesson could be carried into music to talk about tone and pitch. The different noise makers that the students use should be varied enough so that they can see the difference in the pattern on the wall to see the pitches, tones, etc. The website http://www.sciencehouse.com/toolkit-experiments.html is a good tool for this activity. It has a picture and some ideas that go along with this lesson.
When they are finished building it, they should explore on their own to try and figure out what it is and how it works. Aside from giving them the building materials, I wouldn't give them any other directions until it is necessary.
After students have explored with the oscilloscope, I would have some whole group discussion to see where they are at and make sure all students are on the same page.
I would have previously gathered some noise makers (everything from instruments, toys, music, etc.) for the lesson. I would have students use a variety of the different noises and observe what kind of pattern comes from the beam. If it's possible for students to have access to a computer with speakers, they could also use a variety of music types. If students don't have access to computers with speakers attached, I would have a group demonstration so that they can see the different patterns that music makes. I would demonstrate a variety of types of music. Classical, jazz, and Broadway music make great patterns on the wall. I would also use music that they are interested in as long as it was appropriate.
I would have students document the different patterns that they saw, describe some of the differences. Discuss why they thought some of the patterns were made, etc. This is going to change depending on the different goals that you have for the lesson. There are also a few online demonstration videos you could view with the class after they have finished if you wanted to add more to the lesson or have some more whole group discussion as well.
In closing I would discuss how this relates to what students have been learning about sound and sound waves. This lesson could be carried into music to talk about tone and pitch. The different noise makers that the students use should be varied enough so that they can see the difference in the pattern on the wall to see the pitches, tones, etc. The website http://www.sciencehouse.com/toolkit-experiments.html is a good tool for this activity. It has a picture and some ideas that go along with this lesson.
Teaching Notes and Tips
I think that this would be best completed in small groups because there are some great discussion opportunities. The oscilloscopes could be pre-made to save time for the lesson though it is a fun learning opportunity for students. Students won't each get their own oscilloscope if done in a group but they don't NEED to have their own (it would probably just get thrown away). Make sure there are no sharp edges on the mirrors so that students don't get cut.
Assessment
Assessment would be done using their discussion notes from their small groups, the observations that they made and documented and any other additional sheets or handouts that could be added to this lesson to make sure the students got the understanding that you wanted them to get out of the lesson.
Standards
If students build an oscilloscope, the practice of science and engineering standard could be used.
8.2.3.1.1 waves
6.2.3.1.2 sound waves
3.2.3.1.1 pitch and sound
8.2.3.1.1 waves
6.2.3.1.2 sound waves
3.2.3.1.1 pitch and sound