Beacon Lesson Plan Library

A Bubble Full of Math

Rita Williams


This is a fun way for students to compare estimated lengths with actual lengths.


The student estimates the measure (length, weight or mass, and capacity) of an object or figure and then compares the estimate with the actual measurement of the object or figure.


You need the following materials for each pair of students:
-Container of at least 4 fl oz of bubbles
-Black construction paper
-1 ft-long piece of string
-Ruler (metric)
-Copy of the student lab sheet with rubric on the opposite side (See Associated File)


1. Gather materials.
2. Make sure you understand the directions the students are going to have to follow.
3. Find a suitable place outside of your school where students can do the lab.


1. Put students in pairs. Review your rules on how to be a cooperative worker. Encourage them to work cooperatively with each other throughout the activity, and let them know they will be assessed on how they interact with each other.

2. Ask them if they could tell you how tall you are. Some of them will probably yell out some figures. (If they do not, encourage them to do so.) Have a brief discussion on how they came up with their answers. Make sure the word “estimation” comes up. Next, tell them your actual height and briefly discuss the difference in the estimated and actual answer. Inform them that they are going to go through the same process with the sizes of circles by blowing bubbles.

3. Distribute a lab sheet, with the rubric copied on the opposite side, to each pair. (See Associated File)

4. Walk them through the lab procedures and answer any questions.

5. Review the rubric with the students and answer any questions.

6. Distribute 1container of bubbles, 1 piece of black construction paper, 1 ft-long piece of string, and 1 ruler to each pair of students. Make sure each pair of students has at least one pencil between them.

7. Take them to the outside location where they are going to do the lab.

8. Instruct students to perform steps 1-6 on the lab sheet.

9. If students finish with time to spare, allow them to freely blow the bubbles.

1. Briefly review the activities from Day 1.

2. Instruct students to complete step 7 on their lab sheet.

3. Give students time to answer the 3 questions at the bottom of their lab sheet. They may do so on the bottom of the opposite side.

4. Have a discussion based on Questions A, B & C.

5. Collect their lab sheets.


Each pair of students completes the attached math lab sheet. Lab sheets are assessed using the attached rubric. (See Associated File)


This activity could be used to introduce circumference, diameter, and radius. Explain to students that the string actually measured the distance around the circle, which is the circumference of the circle. Tell the students that the circumference can also be found by using the formula C = 2(pi)r. The students can measure the radius of each circle, plug it into the formula and see if they obtain an answer that is close to the measures on their lab sheet.

Web Links

This site is an index and allows you to choose the topic in which you are interested. Four levels of fractions, etc. are presented, including information as well as practice.
The World of Math On Line

Attached Files

This file contains the lab sheet and rubric.     File Extension: pdf

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