Erin Jamieson

Kathleen Hogan

Education 140

November 17, 2005

Mr. Robinson’s Classroom

St. Vincent Pallotti School

1.)  Objectives

  1. To learn about the difference between convex and concave lens and why they produce certain types of images through the use of a camera obsura.

2.)  Grade Level

  1. Eight grade

3.)  Outline of procedure

  1. Steps involved
  2. Give background information on the camera obscura
  3. Explain to students what the camera obscua means. IT means darkroom. Its been used in art because it produces 3-D images. Scientist have used camera obscuras to view sunspots and solar eclipses. The biggest scientific finding is that scientist have found that the camera obscura acts like the human eye.
  1. Review lens – t-chart of concave/convex lens, and also write down the definition of real and virtual images.
  2. See terms under scientific content
  1. Activity
  2. Break students into pairs
  3. Give each pair a shoebox, tissue paper, tape, and a lens
  4. Have students follow along with the teacher as they demonstrate how to construct a camera obsucra.
  5. Have the students work on a handout and answer questions.
  6. Then have the students use the light source to view their object. Have the students draw what they see on the worksheet and explain why they think the image is the way it is.
  7. Bring class back together for a discussion. Ask if anything has changed since their predictions. Have the students explain why they think they saw what they saw. Have students explain the type of lens that was used and why they think it was that type of lens.
  8. Materials needed
  9. Shoe box
  10. tape
  11. tissue paper
  12. magnifying glasses
  13. light source
  14. coke can
  15. other objects to view
  16. Safety requirements
  17. Students need to be careful around the light source and make sure they do not get to close. Do not touch the light bulb.
  18. Students need to be careful with the magnifying glass.

4.)  Teacher role in the activity

a.  The teacher’s role in this lesson is to prompt students’ thoughts with questioning. They will initiate student discussions, and facilitate classroom discussion. The teacher should make sure that all groups are on task, and understanding what they are learning. The teacher will model how to construct the camera obscura, and also assess the students’ experimenting with the lense and collect students’ worksheets to assess as well.

5.)  Students role in the activity

  1. The students will listen to and apply terms given during the introduction to the lesson. The students will collaboratively work together to construct and use the camera obscura. They will make predictions and through the activity clear up any misconceptions that they may have. Students are also required to complete the worksheet given to them before the activity so they can participate in both small group, and whole class discussion.

6.)  Scientific Content

a.  Background Information:

  1. Concave
  2. Is thinner in the center than around the edges, it is shaped like a bowl
  3. Parallel rays of light go straight into the lens and as they go through the lens they spread out and go parallel. Lights rays NEVER meet.
  4. Concave lens can only produce virtual images.
  5. Virtual images- are up right images.
  1. Convex
  2. Is thicker in the center then around the edges
  3. When parallel light rays go through the lens and then come together at a focal point.
  4. Focal point- is the point where light rays come together after traveling through a lens.
  1. Convex images can produce either a virtual image or a real image. The image the convex lens produces depends on the distance it is from the focal point.
  2. Virtual images are produced if the object is between the lens and focal point

ii.  Real images are produced if the object is further away from the focal point.

  1. List References:
  2. Students’ Textbook: Prentice Hall: Science Explorer- Sound and Light. –this was used not only to obtain the terms needed to teach this lesson, but also if students need to follow along in the book they can do so as well.
  3. http://www.acmi.net.au/AIC/CAMERA_OBSCURA.html -- This provided information on the history of the camera obscura.
  4. Marquette ARSC Lab – We used one of our old labs to get ideas of different objects to use in the camera obscura.

c.  Rational for use of terms:

i. The reason that we introduced all of these terms is because in the camera obscura that we are constructing, we are using a convex lens. The rationale for teaching about real and virtual images are because the students should be seeing a real or inverted image on the tracing paper of the camera obscura. If the students are between the focal point and the lens, then they will see a virtual image of the object on the tracing paper. Therefore it is important for students to understand focal point, and what types of lenses (both convex AND concave) can produce virtual images.

7.)  Visual Aids

  1. There will be white board hand drawings of concave & convex lenses, virtual & real produced images, and focal point. The students will also create their own visual aid of what image was produced after looking through the camera obscura.

8.)  Motivational Quality

  1. Students will be motivated to learn because they will be participating in a hands on activity in which they will be working with a partners. Will also be motivated by choice because they will be allowed to pick a few images to look at during the investigation stage of the lesson.

9.)  Learning Styles

  1. Visual- chalk board, white board, pictures, activity (able to view object)
  2. Audio- class discussion. pair discussion, teach talk through out lesson
  3. Kinesthetic- hand on activity, moving around the class to work with a partner, drawing the visual

10.)  Assessment

  1. Assess students through their participation in the activity, classroom discussion, and their worksheet.