Purpose:
- Model how the size of a pupil affects how much light enters an eye.
Standards:
- Science: NGSS: 4-PS4-2: Develop a model to describe that light reflecting from objects and entering the eye allows objects to be seen.
Learning Objectives:
- Students will understand that the size of the pupil affects how much light enters an eye.
- Students will make a model of an eye to test their ideas.
- Students will graph their data to look for patterns.
Materials:
- Paper to make eye model, either:
- Mobile devices, one for each group of students.
- Google Science Journal app installed on mobile devices.
- (Optional) A flashlight for each group of students.
Vocabulary:
Media Resources:
Pre-Lesson Activities:
- Ask several students if they can bring in their mobile phone to use for this experiment. You will need one phone for each group of four to six students.
- Ask the students to install the Google Science Journal app (free) the night before so parents can give permission and enter any passwords needed to install the app.
- Make copies of the Eye Model Diagram, one for each group of students, if you are using this diagram in the lesson. Also make copies of the data collection note page, one copy for each student.
Lesson Activities:
Part 1 - Video Review
- The parts of the eye.
- How light enters the eye through the pupil.
- How the pupil size changes.
- Why the pupil would change size.
Part 2 - Set up
Place students into groups of three to six students.
Give each group of students a copy of the
Eye Model Diagram and a flashlight (optional).
Give each student a copy of the
data collection note page. Have students make a prediction about how pupil size will affect the amount of light entering the eye.
- Have students fold the eye model on the lines, then have students cut the dotted lines near each corner of the page.
- Have students fold the paper so that a box is formed and the circles are facing up.
- The tabs of the box model do not need to be taped so that it’s easier to cut out the circles later.
- Ask students what this paper box is modeling (an eye) and what the circles will model (pupil).
Have each group get out their mobile phone and open the Science Journal app.
- Show students how to press the + button to start a new experiment.
- Have students press the Circle with a wavy line icon to start collecting data.
- The Ambient light sensor is automatically selected.
- Have students press the Information icon to learn about the lux unit.
- Tell students that they will press the red Record button at the bottom of the screen to record a lux reading, and pressing the button again will end the recording.
- Also tell students that they will need to start recording, then turn off the phone screen so that the light from the screen doesn’t affect the experiment.
- Have students collect a sample recording to test out it works.
- Have students press the recording they just collected, which will be at the top of the app.
- Have students tap the “three-dot” overflow menu, then select Crop.
- Have students practice dragging the sliders on each end, then press the Check button to crop the recording.