Peer Instructor Reflections
Going on Another Field Trip to Observe the Sky
Written by: Katie Rodriggs
As the students got into class, I asked them to pull out their moon journals and to discuss their observations with their small groups. Then they noted their stick figure drawings of the moon, sun, and angle of the moon and sun on our collective moon calendar. I was surprised to hear that most students saw that the moon was getting smaller, but the angle between the moon and the sun was getting larger. I kept hearing that students couldn’t see the moon, or the angle was getting larger, until I got to the last table. The girl said, “I must be wrong but I noticed the angle getting smaller along with the moon getting smaller”. Throughout the class I noticed more students doubting their ideas and observations just because they were different from the rest of their peers, although a majority of the time these were the students that were correct.
Outside we were pleasantly surprised to see the moon! Barely visible, the moon was a waning crescent. Most of the class saw it as well, made notes in their moon journals and made predictions for what they believe the moon will look like next. Most students thought they wouldn’t be able to see the moon in a few days, then it would begin to grow again. They believed this because they noted the moon was shrinking along with the angle between the moon and the sun, so they figured this pattern would continue. These observations were very insightful!
I showed the students how to mark their shadow plots, marking on the paper where the paperclips shadow landed. The students were able to see the shadow moved to the East as the sun rose higher, in 15-minute increments. As we were doing this, with a partner the students traced their partner’s feet and shadows with chalk, then guessed where the top of the shadow will be at the end of class. They used their shadow plots to make a reasonable guess as to why their shadow would move in that manner. (All had chose west and shorter). After the students made their predictions marking an X on their predicted spot, they video taped each other, explaining to the camera their reasoning behind their prediction. At the end of class, we went back outside to see where their shadows landed. They took pictures of how close they were to their prediction.
Exploring Pinhole Phenomena
Written by: Nathalie Gaebe
I first asked the class if anyone had experience working with a pinhole camera. One student shared her experience working with a pinhole camera and used photo paper to burn an image into it. I demonstrated to the class how to make a pinhole camera using a toilet paper roll, a piece of wax paper, a piece of foil, two rubber bands and a push pin. I laid the foil flat on one open side of the toilet paper roll and the wax paper over the other side. I secured these with a rubber band. I poked a hole in the center of the foil with the pushpin. I demonstrated that the students would point the foil end of the toilet paper roll toward a light and observe what they saw. I prompted them to move their head side to side and adjust the distance from the pinhole and the light and make observations.
The groups came up one at a time and made observations without discussing what they saw. After each group had a chance to observe, they went back to their small group and discussed what they thought was happening with the pinhole phenomenon. Some groups believed that the foil reflected the light inside of the tube or predicted that the wax paper would completely light up like a flashlight. We had the groups draw the situation using their eye, a pinhole camera, and the light bulb. After they completed their picture, Emily, Katie and I worked with small groups to help them understand what was happening with the light rays and the pinhole to create the projection of an upside down light bulb. The groups then used their other whiteboard to draw a ray diagram that demonstrates why the light bulb appears upside down.