#2991. Reflecting Light

, level: all
Posted Tue Dec 2 16:42:18 PST 2003 by Rita Scheopner (ritas44@hotmail.com).
Fort Hays State University, Hays, Kansas

Reflecting on Light
Description: Cooperative Learning!
Subject: Science and Technology
Duration: 40 min
Grade Level: 4


Peters, J.M., Gega, P.C.(2002). Science in Elementary Education. New Jersy: Merrill Prentice Hall.
Tobecksen, Alan, Henry Clay Elementary School. (http://www.iit.edu)
Hearns, Lyvoonia, Randolph, A. Philip (http://www.iit.edu)

Students will apply process skills to develop an understaind of physical science including: properties, changes of properties of matter, motion and forces, and transfer, and transfer of energy.

The students will understand and demonstrate the transfer of energy.

The student uses concepts and procedures of data analysis in a variety of situations.

The student generates, organizes, and interprets rational number and other data in a variety of situations. The studen applies measures of central tendency when drawing conclusions from the data.

Students will use mirrors to reflect light and hit a target in a separate part of the room.

Students will cooperate in the use of multiple mirrors to hit a target in less than twenty seconds

Students will answer at least 5 out of seven questions correctly on a quiz.

Introduction of Topic: Ask students how a mirror works. Keep giving them time as well as open-ended answers that influence them to think about it.

Development of the Core:

1. After student have exhausted all possible answers, introduce them to the three properties of light

2. Show them how light is refracted into a color spectrum as it passes through a prism.

3. Show them how light is absorbed into a dark piece of material

4. Show them how light is reflected off a mirror.

5. Inform students that the angle light hits an object is the same angle it is reflected away.

6. Have students order themselves with the following jobs in conjunction with the month of their birthdays.

I. Time Keeper

II. Target stand

III. Emitter

IV. Reflector

7. After everyone has been assigned a job, have him or her come up and retrieve his or her equipment.

8. When the instructor says go, the reflector, emitter, and target are to run to their stations and the object is to reflect the light onto the target in the quickest time. Each reflector will get three attempts.

9. Have that person average their times.

10. Have team members exchange positions starting with the eimitter going to the reflector, reflector to the target, target to the time, and time to the emitter.

11. HAve the students each take three turns and average their scores

12. After all students have had their turns, assign all students a mirror

13. Position the eimitter in a location, target in a different location, and have the students stagger themselves, 1,2,3,4,. The first person reflects the light to the #2. That person reflects it to #3 amd that person #4. #4's job is to hit the target.

14. Have them do this four times with each person switching positions as before.

15. Have them average their times.

16. Have students sit down in their cooperative groups.

17. Give them about 2 minutes to discuss what they discovered about light refleciton.

18. Have them explain how they knew which angle to hold the mirrors.

19. Introduce students to the LDO Theory.:Light dies out and stops as it travels further from its source. This distance is different for different light sources.

20.Introduce students to the LGF Theory: All light goes forever, until it is absorbed.

21. Divide students into groups of two by their average refleciton times.

22. Have students write their reasons down so that they can defend their thoughts in tomorrow's activities.

23. Hand out quizzes to the students

24. Inform students that after they are finished taking their quiz, to turn it over and write one thing they did well as a cooperative group and one thing they need to improve on.

(RETEACH) IF students needed an extra lesson to better understand the reflection, refraction, or absorption properties, redo the three demonstrations that were used at the beginning of the lesson. Then have the students use a protractor to measure the angle of the light to the mirro and the angle of the reflection. You could also use a couple of small 2" x 2" mirrors to make a small periscope to illustrate the reflection property.

(ENRICHMENT) Have the students examine different geometric shapes and discuss lines of symmetry. The students could then use the mirrors to divide the shapes on suspected lines of symmetry and determine if they actually were. They could do predictions before they actually used the mirrors. Have them write the number of different lines of symmetry each geometric shape has.

Pre-requisite Skills: You can define ways that additional content areas could be included.

Materials: Four mirrors (approx. 5"x 7"), flashlight with high-beam concentration, cardboard with black material, crystal or prism, material to use as a target, blackboard or dry-erase board, paper and pencils.

Group Size: 3-4 students

Group Roles: Reflectors, Materials gatherer, Timekeeper, Target stand, Emitter, and Assessment collector are all possible roles depending on group size