Measuring Volume with Water

Lesson Plan #: AELP-PHY0208

An Educator's Reference Desk Lesson Plan

Submitted by: Molly Kolodejchuk and Patricia Dihle
Email: mollymontana79@hotmail.com, trishdihle@yahoo.com
School/University/Affiliation: The University of Montana
Endorsed by: Lisa Blank
The University of Montana, Missoula

Date: December 9, 2002

Grade Level: 6, 7, 8

Subject(s):

Science/Physical Sciences
Mathematics/Measurement

Duration: 1 hour

Description: Rocks and other solid objects have many different shapes. Sometimes it is hard to tell which of two different-shaped objects takes up more space. (The amount of space an object takes up is its volume.) How can you compare the volumes of small solid objects?

Goals: National Science Education Standards (NSES) :

Content Standard A (Science as Inquiry):
- Develop descriptions, explanations, predictions, and models using evidence.
- Think critically and logically to make the relationships between evidence and explanations.
Content Standard B (Physical Science): As a result of their activities in grades 5-8, all students should develop an understanding of
- Properties and changes of properties of matter
- Motions and forces
- Transfer of energy
Content Standard G (History and Nature of Science): As a result of activities in grades 5-8, all students should develop understanding of
- Science as a human endeavor
- Nature of science
- History of science

Objectives:

Students will make predictions about volume and be able to support their predictions.
In small groups, students will be able to conduct an experiment to determine the volume of five small rocks.
Using data from their experiments, students will be able to explain what volume is.

Materials:

five small rocks for each group
rulers
oil-based modeling clay
large clear jars/beakers with straight sides
rocks
water
masking tape
pencils
fork or spoon
paper
Prediction Sheet and Data Sheet

Handouts in .pdf format; requires free Adobe Acrobat Reader.

Click the icon to obtain the free Reader.

Procedure:

Focus Phase:
Show two different shaped boxes. Ask students, "Which box has more volume? Why? How do you know?" Discuss ways to find the volume of a six-sided figure. Present an odd shaped object and ask how students might find the volume of an object without definable sides. If students are stuck, ask them what happens to the water in the bathtub when they get in. (Their body displaces water.) Then present the class with two similarly sized objects (a rock and a pine cone) and ask, "Which object has more volume?" Have students predict on their prediction sheet (see Materials ) which object will displace more water and why. Record students' predictions on the board and discuss their reasoning. Using the two objects, model the procedure for the challenge phase.

Challenge Phase:
Divide the class into small groups. Each group needs five small rocks, masking tape, a jar/beaker, pencils, ruler, fork/spoon, and data sheets. The students should place a piece of tape lengthwise along a jar/beaker already filled halfway with water. With a ruler and pencil they should make evenly spaced marks on the jar's tape strip. Each mark will be one unit. On their handout, students record the level of the water. Then they place one rock in the jar. They should record the new water level. Students remove the rock and continue the same procedure for the remaining rocks.

Concept Introduction Phase:
Ask students about the data they gathered and what conclusions they discovered from the data. Record their answers on the board next to the focus phase answers. Ask, "What do you think determines the amount of water displaced?" Students will now experiment with modeling clay. Give students about 10 minutes to make different shapes with their allotted clay. Students should record the shapes that they made and how much water they displaced. After students have experimented ask, "Does size make a difference? Does shape make a difference? Does mass make a difference?"

Conclusion:
Mass is independent of volume. By having two objects that have the same volume but different masses, one can tell that mass is not a factor in water displacement.

Concept Application:
The volume of different shaped solid objects can be compared by the water each object displaces. Have students rank their rocks from largest to smallest in volume.

Assessment: Informally observe students during the experiment and class discussions. Analyze the responses on students' prediction sheets. Students should write a paragraph about what volume is and include examples from their data.

Useful Internet Resource:
* National Science Education Standards (NSES)
http://books.nap.edu/html/nses/

Other Reference:
Peters, J. & Gega, P.C. (4th ed.) (2002). Concepts and inquiries in elementary school science . Columbus, OH: Merrill Prentice Hall