Wonderful World of Worms
Students will describe the differences between real and artificial worms. Students will measure the worms and compare their lengths.
Introduction (5 minutes)
- Introduce the concept of earthworms to your students. Allow them to ask questions about earthworms, such as where they live.
- Show your students real worms and artificial, or fake, worms. For this lesson, you can describe real worms as ones that are living or have been alive in the past.
- Help them describe the differences between a real and artificial worm. Write their answers on the board, if desired. For example, possible answers include: Real worms are slimy. Real worms move. Artificial worms do not move.
- Using rulers, show your students that they can use this tool to measure, or determine the length of something. Show them the inch numbers on the ruler, explaining that one way to measure is with inches.
Explicit Instruction/Teacher Modeling (5 minutes)
- In front of the class, lay a real earthworm on a ruler, and determine its length in inches.
- Show your students how to identify the length of an earthworm, and write the number of inches you measure on the board.
- Tell your students that they can find the nearest number on the ruler to identify the worm's length. Inch rulers without smaller fractions will work best for young students.
- Your students might not be ready to use rulers, so you can also have them visually compare the worms to decide which one is longer.
Guided Practice/Interactive Modeling (5 minutes)
- Invite a student to put a worm on a ruler and identify its length. Then, have another child repeat with her worm.
- Discuss which worm is longer or shorter with the class. Explain to the class that they are going to compare the size of earthworms by deciding which one is longer or shorter. Possible discussion questions include: About how many inches is your worm? When you put them next to each other, which one looks bigger?
Independent Working Time (30 minutes)
- Give each pair of students a small handful of worms (real or artificial) and a ruler.
- Allow your students to explore the materials for a few minutes. Give them magnifying glasses to investigate their worms closely.
- Make sure your students are holding their worms straight, as the live ones might move around too much to measure.
- Have your students measure their worms and arrange their group of worms from shortest to longest. If you are letting your students use live worms, have them contain them on their desks.
- Enrichment: For students who are advanced, have them say aloud how long their worm is. Have them look at the whole numbers on the ruler (one inch, two inches, etc.) and approximate the length of each worm. For example, if a worm is actually 5.75 inches, tell your students to look at the biggest whole number.
- Support: If students are struggling to use the ruler, have them compare the words visually using an existing object, such as the length of a pencil.
Assessment (10 minutes)
- Go around the room as students are working, and visually assess whether they are able to identify short and long worms.
- If students are having trouble using the ruler, tell them to visually assess the worms' lengths as well.
Review and Closing (10 minutes)
- In closing, have children present their longest and shortest worms.
- Create a visual graph on the board of the shortest and longest worms to show which pair has the tallest and shortest worms in the class.