Discuss the role of models in science and relate it to the models of the eye and the ear that students design in this section.
Draw students' attention to the Key Ideas using means such as posters and overhead transparencies.
Assign Mini Activity: How Much Sleep Do You Need?, which requires making observations over a two-week period.
Begin the section by discussing the question, “How do you know about the world around you?”
Emphasize that all electrical messages transmitted by sensory neurons are the same. The sensation that is experienced is determined by where they go in the brain.
Introduce Activity 5 -1: Using Your Sensors by discussing the questions “What is sensation?” and “What are sensors?”
Discuss Activity 5-1 Report questions in class.
Use the student-constructed 3-D model of the eye to illustrate how the eye works similar to a camera.
Completion of eye model in Activity 5-2 helps students with the dissection of the eye in Activity 5-3.
Discuss Activity 5-3 Report questions.
Complete Enrichment 5 -1: Building a Model of the Ear, if time permits.
Emphasize good health practices as they relate to the senses, especially the eyes and ears.
Time permitting select from unit projects.
Throughout and at the end of the section refocus students' attention on the Key Ideas.
Your brain associates a sensation with stored information in your brain memories. Write a journal entry about your favorite color. Include descriptions of how the color might feel, taste, smell, and sound. What association does your brain make with your favorite color?