How long is your smile?

Students will use standard and nonstandard measurement to measure their smile.

A lesson plan for grade 3 Mathematics

By Julie Little

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Learning outcomes

Students will learn how to use standard and nonstandard measurement tools (rulers and string) to measure their smile.

Teacher planning

Time required for lesson

45 minutes

Materials/resources

• red yarn
• paper plates
• crayons
• scissors
• ruler
• glue
• index cards

Technology resources

None

Pre-activities

Students would need to know: what a ruler is, and the form of measurement used (cm or inches).

Activities

1. Talk to the students about how we can decide how long something is. Tell them that we use different scales to measure length. We can use inches, feet, and yards, or we can use centimeters, meters, and kilometers.
2. Choose a form of measurement (customary or metric). Tell the students that today you are going to learn how to measure using either customary or metric units. Then, review how to use a ruler. (Students may need to know which end of the ruler to put down and where to put the ruler when measuring.) Use the overhead or white board to measure an object. You can draw an object on the board and then use your own ruler to measure the object to show the class.
3. Allow the students to come up and measure different objects on the board or the overhead. You may also want to have them measure individual ojects at their desk. Go around and watch the students measuring their objects to make sure they are doing it correctly.
4. Once the students have finished the guided activity, hand out materials to measure their smile. Give each student about a foot of yarn, and a ruler. Allow the students to work in partners. Then, have the students to help each other put the yarn on their smile. Tell everyone to SMILE! One end of the yarn should go on one side of the smile and the other should have left-over yarn. The students should place their index finger and thumb on this portion of the string. While holding the string in their fingers, they should take the string down and cut the string where their fingers are holding it.
5. Have the students straighten out the yarn and measure the length of the smile using a ruler. Have the students to write the length of their smile on an index card. The “smiles” can be glued on a paper plate in the shape of a semi circle and the student can create a face on the plate with crayons and other materials chosen by the teacher.
6. Last, go around the class and ask how long everyone’s smile was. Take the measurements and add the smiles on the board to see how big your class’ smile is altogether. You can cut a large piece of yarn to show how long this would be.

Assessment

In order to assess the student’s ability to meet the lesson goals, use the following rubric.

Supplemental information

None

Related websites

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Comments

The ideas for this lesson plan were inspired by a collaboration of my colleague, S. Shepherd, and I during a unit on measurement.