# A Mass of Pennies

### Summary

Students will estimate and determine the number of cents (pennies) that are needed to equal the mass of a variety of common objects.

• Cent

• Generic

### Objectives

• Students will understand the definition of "mass."\
• Students will develop a process for measuring and will explore concepts related to units of measurement.
• Students will make and use estimates of measurement.

• Science

### Class Time

Sessions: One
Session Length: 45 minutes
Total Length: 0-45 minutes

• Whole group
• Small groups

• Cent
• Coins
• Estimation
• Mass
• Measurement
• Penny

### Materials

• “How Many Pennies” recording sheet
• \$2.00 in cents (pennies) for each student group of four
• Common items: walnut, ping pong ball, crayon, eraser, pencil, small stone, a shell, felt marker, balance or scale

### Preparations

Download and make copies of the “How Many Pennies” recording sheet from lspace.learningspace.org/usmint/howmanypennies.html.

1. Review the term “mass” with your students. The term can be used interchangeably with the term “weight,” but more specifically an object’s mass is the amount of material in an object that causes it to have weight.

2. Divide students into groups of four. Give each group a “How Many Pennies” recording sheet, \$2.00 in cents (pennies), an age-appropriate balance or scale, and a tray containing the “Common Items” listed under Materials.

3. In their groups, have the students use their own “body balance” (comparing the weights in their own hands) to estimate the number of cents (pennies) it will take to equal the mass of each item on their tray. The students should record their estimate on the “How Many Pennies” recording sheet.

4. Have the students use the balance and the pennies to measure the mass of each object and record their findings.

### Differentiated Learning Options

For more advanced students, have them weigh one penny and then weigh each object. Have them use this information to see if they can figure out how many pennies it would take to equal the mass of each object.

Evaluate the students' responses on the “How Many Pennies” recording sheet to see whether they have met the lesson objectives.

There are no related resources for this lesson plan.

This lesson plan is not associated with any Common Core Standards.

Discipline: Mathematics
Domain: 3-5 Number and Operations
Cluster: Compute fluently and make reasonable estimates.
Standards:

In grades 3–5 all students should

• develop fluency with basic number combinations for multiplication and division and use these combinations to mentally compute related problems, such as 30 × 50;
• develop fluency in adding, subtracting, multiplying, and dividing whole numbers;
• develop and use strategies to estimate the results of whole-number computations and to judge the reasonableness of such results;
• develop and use strategies to estimate computations involving fractions and decimals in situations relevant to students' experience;
• use visual models, benchmarks, and equivalent forms to add and subtract commonly used fractions and decimals; and
• select appropriate methods and tools for computing with whole numbers from among mental computation, estimation, calculators, and paper and pencil according to the context and nature of the computation and use the selected method or tools.

Discipline: Mathematics
Domain: 3-5 Number and Operations
Cluster: Understand meanings of operations and how they relate to one another.
Standards:

In grades 3–5 all students should

• understand various meanings of multiplication and division;
• understand the effects of multiplying and dividing whole numbers;
• identify and use relationships between operations, such as division as the inverse of multiplication, to solve problems; and
• understand and use properties of operations, such as the distributivity of multiplication over addition.

Discipline: Science
Domain: 5-8 Content Standards
Cluster: Unifying Concepts and Processes
Standards:

• Systems, order, and organization
• Evidence, models, and explanation
• Change, constancy, and measurement
• Evolution and equilibrium

Discipline: Mathematics
Domain: 3-5 Number and Operations
Cluster: Understand numbers, ways of representing numbers, relationships among numbers, and number systems.
Standards:

In grades 3–5 all students should

• understand the place-value structure of the base-ten number system and be able to represent and compare whole numbers and decimals;
• recognize equivalent representations for the same number and generate them by decomposing and composing numbers;
• develop understanding of fractions as parts of unit wholes, as parts of a collection, as locations on number lines, and as divisions of whole numbers;
• use models, benchmarks, and equivalent forms to judge the size of fractions;
• recognize and generate equivalent forms of commonly used fractions, decimals, and percents;
• explore numbers less than 0 by extending the number line and through familiar applications; and
• describe classes of numbers according to characteristics such as the nature of their factors.

Discipline: Mathematics
Domain: 3-5 Measurement
Cluster: Apply appropriate techniques, tools, and formulas to determine measurements.
Standards:

In grades 3–5 all students should

• develop strategies for estimating the perimeters, areas, and volumes of irregular shapes;
• select and apply appropriate standard units and tools to measure length, area, volume, weight, time, temperature, and the size of angles;
• select and use benchmarks to estimate measurements;
• develop, understand, and use formulas to find the area of rectangles and related triangles and parallelograms; and
• develop strategies to determine the surface areas and volumes of rectangular solids.

Discipline: Mathematics
Domain: 3-5 Measurement
Cluster: Understand measurable attributes of objects and the units, systems, and processes of measurement.
Standards:

In grades 3–5 all students should

• understand such attributes as length, area, weight, volume, and size of angle and select the appropriate type of unit for measuring each attribute;
• understand the need for measuring with standard units and become familiar with standard units in the customary and metric systems;
• carry out simple unit conversions, such as from centimeters to meters, within a system of measurement;
• understand that measurements are approximations and how differences in units affect precision; and
• explore what happens to measurements of a two-dimensional shape such as its perimeter and area when the shape is changed in some way.

Discipline: Science
Domain: K-4 Content Standards
Cluster: Unifying Concepts and Processes
Standards:

• Systems, order, and organization
• Evidence, models, and explanation
• Change, constancy, and measurement
• Evolution and equilibrium
• Form and function

Discipline: Science
Domain: 5-8 Content Standards
Cluster: Science as Inquiry