Click to begin music – play as students engage.

Explore the sphere. What do you discover? Engage Students should discover that a sphere magnifies and turns the object being observed upside down. Students may add other comments. This builds background knowledge. Extend by having them look at a cube and a cylinder, then compare what they learn with what they know about a sphere. Students should discover that the flat side of the cylinder and the cube do not change the appearance of the object. They will also discover that the round side of the cylinder magnifies and turns the object being observed upside down.

Lenses Title page

Study the lens at your table: How is the lens shaped? Look through the lens at the pages of a book, your hand, a hair, and other things. Draw and label what you see in your science notebook. How does this lens make things look? Explore Put convex lenses on each table. Guide students through the steps on the slide. Students will also need a flashlight and white paper. The shape of the lens is curved outward in the middle and thin on the sides. Students may have variations. Students will draw and label 4-5 items that they observe under the magnifying lens. Students should complete this sentence stem – This lens makes things look (larger and upside down).

Shine a flashlight on a piece of white paper. Draw what you see. Shine a flashlight through the lens onto a piece of white paper. In what direction does this lens bend light? Shine the flashlight through different combinations of lenses. What happens when you use multiple lenses at the same time? Draw pictures of what you see in your science notebook. When students shine the light on the paper they will see the light is evenly spaced in a circle. When students shine the light through the lens on the paper the brightest spot will be in the center. Ask students what that means. (It means that the lens bends the light towards the center.) Convex

How does that apply to the light going through the lens? What does focus mean? How does that apply to the light going through the lens? Make a scientific drawing of what happens when a light goes through this type of lens. Explain Focus means to bring to a point, make clear, sharp, not blurry. The light rays are focused towards the center of the circle of light. Click to bring in scientific drawing. Click to bring in the labels: Light Rays, Convex Lens, Focus Point Convex Light Rays Focus Point Convex Lens

makes things look larger through them. A Convex Lens… has at least one surface that curves outward like the exterior of a sphere. makes things look larger through them. brings light rays to a point or focus (converge). Explain Read and discuss. Convex

Normal Vision Light enters the eye and the convex lens of the eye focuses the image on the back of the eye (retina). Explain Read and discuss. Convex

Farsightedness occurs when the eye is too short or the eye’s cornea is flatter than normal. This causes light rays to focus beyond the back of the eye (retina) creating blurry close-up vision. Extend Read and discuss. Click to bring in diagram. Read and discuss. Convex

Farsightedness and Convex Lenses Extend Read and discuss. Convex A convex lens makes objects look larger and farther away. Convex lenses correct farsightedness.

Lenses Title page Part 2

Study the lens at your table: How is the lens shaped? Look through the lens at the pages of a book, your hands, a hair, and other things. Draw and label what you see in your science notebook. How does this lens make things look? Explore Put concave lenses on each table. Students will also need a flashlight and white paper.

Shine a flashlight on a piece of white paper. What do you see? Shine a flashlight through the lens onto a piece of white paper. What do you see? Shine the flashlight through different combinations of lenses. What happens when you use multiple lenses at the same time? Draw pictures of what you see in your science notebook. Explore When students shine the light on the paper they will see the light fairly evenly spaced in a circle. When students shine the light through the lens on the paper they will see a shadow in the middle and a circle of light on the outside. Concave

How does that apply to the light going through the lens? What does diverge mean? How does that apply to the light going through the lens? Make a scientific drawing of what is happening when light shines through this type of lens. Explain Concave Diverge: To spread out; to go in different directions from a common point. Click to bring in scientific drawing. Click to bring in labels: Light Rays, Concave Lens Light Rays Concave Lens

is thicker on the edges than in the middle. A Concave Lens… is thicker on the edges than in the middle. seems to cave in toward the center and things look smaller through them. make light rays bend outward (diverge), spreading them across a surface. Explain Concave Read and discuss.

Normal Vision Light enters the eye, and the convex lens of the eye focuses the image on the back of the eye (retina). Extend Concave Read and discuss.

Nearsightedness occurs when the eye is stretched and/or the cornea is overly curved. This causes light rays to focus in front of the retina resulting in blurry distance vision. Extend Concave Read and discuss. Click to bring in diagram. Read and discuss.

Nearsightedness and Concave Lenses Extend Concave Read and discuss. A concave lens makes objects look smaller and closer. Concave lenses correct nearsightedness.

Extend Click to play video explaining how light enters the eye.

Review Review/Evaluate Nearsightedness is corrected with a concave lens. Farsightedness is corrected with a convex lens.

Review Review/Evaluate Vocabulary Converge – Focus, bring to a point, to make clear, sharp, not blurry Diverge – Spread out; branch out; to go in different directions from a common point

Do you know the answers to these questions about lenses or do you ASA Specifications follow this slide as an evaluation. Do you know the answers to these questions about lenses or do you need more Science lab time?

Correct Answer: D

Correct Answer: A

Correct Answer: D

Correct Answer: A

Correct Answer: C

Correct Answer: B

Correct Answer: D

Here’s looking at you, kid. Thanks.