Beacon Lesson Plan Library

Who's the Frog Jumping Champion?

Bess Weber


Who's the Frog Jumping Champion in your class? Students construct a model of a simple machine (lever) to investigate the affect that applied force has on an object (plastic frog). This is a fun, hands-on, investigative activity that incorporates both science and math measurement skills in meeting state standards.


The student knows measurement concepts and can use oral and written language to communicate them..

The student knows the six types of simple machines (screw, inclined plane, wedge, pulley, lever, and wheel and axle).

The student knows that an object may move in a straight line at a constant speed, speed up, slow down, or change direction dependent on net force acting on the object.


-1 meter stick per group
-1 ruler per group
-1 copy of Observation Sheet for each student, 1 for teacher (see attached file)
-1 wooden block (approximately 3” by 3”) per group
-1 plastic frog (all same size) for each student (can be purchased in packages at a novelty store where party items are sold)
-1 copy of Concept Illustration Assessment for each student, 1 for teacher (see attached file)


1. Gather materials for activity.

2. Place one sample of each of the six simple machines on display at the front of the room (screw, pulley, inclined plane, wedge, wheel/axle, and lever). Label each machine with a number but don't name them.

3. Make each student a copy of the Observation Sheet and Concept Illustration Assessment. (See attached files)


NOTE: This lesson only teaches the concept of force applied using a lever. Additionally, students need to have prior practice in measuring to the nearest centimeter using meter sticks. Students should also have an understanding of force, motion, and work.

1. Ask students how far a frog can jump. Ask them what makes one frog (same kind, same size, same weight) able to jump further than another. Write several of the answers on the board. Ask who is the “Frog Jumping Champion” in the class.

2. Have one example of each of the six simple machines on display at the front of the room. (screw, pulley, inclined plane, wedge, wheel/axle, and lever)
Label each machine with a number only, no name. These items can be found in a classroom science kit or in the tool section of a hardware store.

Have the students examine the machines. Ask them which one they think would be the best frog jumping machine. Have them explain their reasons.
On the observation sheet (attached file), there is a place for the students to write the number of the machine that is a lever. They should not write the answer until the lesson is completed, and they have experienced working with the lever.

3. Give each student an observation sheet.

4. Tell students that they are going to investigate what makes frogs (plastic) jump and why some frogs jump further than others. Explain that they are going to construct a model of a lever from which the frogs will jump, and then measure the distance the frogs jump using meter sticks. Go over the sections of the observation sheet with the students giving them examples of how to fill them out. Allow students time for questions concerning activities. Discuss requirements for both the check off section of the observation sheet and Concept Illustration Assessment.

5. Working in groups of four, have students discuss and fill in the prediction section of the observation sheet.

6. Give each group a ruler (lever), wooden block (fulcrum to place at the center of the lever), and a meter stick. Have each group construct a model of the lever using the ruler and wooden block. Demonstrate how the lever works and review the purpose and position of the fulcrum.

7. Have students take turns applying force to one end of the lever to thrust their plastic frogs into the air. Students should use the force of only their index finger applied to the end of the lever for the first jump. Have them use their first two fingers to apply force to the lever for the second jump, and apply the force of their whole hand for the third jump.

As students complete each jump, they measure the distance of the jump using the meter stick and record the length on the observation sheet.

8. While circulating around the room to direct, question, encourage and give feed back, (formative assessment) the teacher has each student measure one of the frog’s jumps while he or she observes. This diagnostic assessment can be done quickly and additional instruction given if needed. Teacher checks off measurement skill on the student’s observation sheet as assessed.

9. When finished recording the results of all jumps, students discuss their observations and thoughts about the activity, what they discovered, and the answer to the question “What makes one plastic frog jump further than another frog"? Students return to their seats to independently write the answer to this question on the observation sheet (attached file). The student’s written answer should effectively communicate that he or she understands the Science concept taught (the affect force has on the momentum of an object when using a lever).

Students also write the number of the machine they identify as a lever.

Students should circle the drawing of the dinosaur/frog lever on the Concept Illustration Assessment sheet (attached file).

Demonstration of measurement skills, summary paragraph, identification of a lever, and circled illustration are summative assessments of the student’s knowledge of the concept taught.

(NOTE) If oral and written language is a barrier for ESL students, the summary paragraph should be omitted as assessment. Use measurement skills assessment if applicable.

Because this activity incorporates multiple intelligences, it is very effective for both ESL and ESE students.


Complete an observation sheet (attached file) to correctly identify a lever, record measurements of distances to the nearest centimeter, and effectively communicate in a summary paragraph an understanding of the Science concept taught (02).

Use critical thinking skills to decide in which picture the frog will jump further (04). Pictures are found on the Concept Illustration Assessment sheet which is an attached file.


Check off assessment section of observation sheet for:
Correct identification of a lever
Satisfactory skill in measuring and recording distances to the nearest centimeter
Summary paragraph that effectively communicates an understanding of the Science concept taught (the affect force has on the momentum of an object when using a lever).

Concept Illustration Assessment sheet-Students circle the correct picture, demonstrating knowledge of the Science concept taught (dinosaur/frog lever).


Read How Do You Lift a Lion? by Robert E. Wells aloud to the class as a follow up activity on the use of levers. This is a wonderful book to expand the students’ critical thinking skills.
Have students list all the levers they find around school and at home. One example would be a see-saw on the playground.

Web Links

This site uses animation to demonstrate and quiz students on the six types of simple machines. It has great interaction! It is geared to 4th grade and up, but with teacher facilitation would be a great introduction or summative tool for 3rd graders.
Simple Machines

Attached Files

Concept Illustration Assessment     File Extension: pdf

Observation Sheet     File Extension: pdf

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