3.MD.2: Measuring and Estimating Mass and Volume

Visual Models to Use

• Measurement Tools - Familiarize your child with kitchen scales (for mass), measuring cups and graduated cylinders (for volume)
• Benchmark Objects - Use common objects as references: a paper clip is about 1 gram, a textbook is about 1 kilogram, a water bottle is about 1 liter
• Comparison Charts - Create visual charts showing the relationship between units (1 kg = 1000 g, 1 L = 1000 mL)

Everyday Activities

1. Kitchen Science

When cooking or baking, have your child measure ingredients using measuring cups and spoons. Discuss the difference between liquid and dry measurements. For example, "This recipe calls for 250 milliliters of milk. Can you measure that for me?"

2. Grocery Store Estimates

At the grocery store, have your child estimate the mass of fruits and vegetables before weighing them. "Do you think this watermelon is closer to 3 kilograms or 5 kilograms? Let's weigh it to find out."

3. Water Play

During bath time or outdoor water play, provide containers of different sizes and have your child predict how many small containers it will take to fill a larger one. "How many cups of water do you think will fill this pitcher?"

4. Comparison Challenge

Gather household items and have your child arrange them from lightest to heaviest (by mass) or from least to greatest volume. Use a scale or measuring cup to verify their predictions.

Strategies When Your Child Struggles

1. Use Concrete Examples

Always start with real objects that your child can hold and measure. Abstract concepts of mass and volume are difficult without hands-on experience.

2. Create Reference Cards

Make cards showing common objects and their approximate measurements:

• A paperclip ≈ 1 gram
• An apple ≈ 100 grams
• A textbook ≈ 1 kilogram
• A teaspoon ≈ 5 milliliters
• A can of soda ≈ 355 milliliters
• A milk carton ≈ 1 liter

3. Connect to Prior Knowledge

Relate new units to ones your child already knows. For example, "A liter is a little more than a quart" or "A kilogram is about 2.2 pounds."

4. Estimation Before Measurement

Always have your child estimate before measuring. This builds their intuition for reasonable measurements.

5-Minute Practice Activities

1. Quick Estimates

Gather five household objects. Have your child estimate their mass in grams or kilograms, then weigh them to check.

2. Volume Puzzles

Fill a container with a known volume of water (e.g., 500 mL). Ask your child to figure out how to divide it equally among several smaller containers.

3. Measurement Riddles

Give clues about an object's mass or volume and have your child guess the object. "I'm thinking of something in our kitchen that has a mass of about 2 kilograms. What might it be?"

4. Quick Conversions

Practice simple conversions between related units: "If this bottle holds 2 liters, how many milliliters is that?"

Mid-Year Expectations

By the middle of third grade, your child should be able to:

• Identify appropriate tools for measuring mass and volume
• Understand the difference between mass and volume
• Know common measurement units (grams, kilograms, milliliters, liters)
• Make reasonable estimates of mass and volume for familiar objects
• Measure mass and volume with guidance

End-of-Year Expectations

By the end of third grade, your child should be able to:

• Independently measure mass using grams and kilograms
• Independently measure volume using milliliters and liters
• Make accurate estimates of mass and volume
• Understand the relationship between related units (g/kg, mL/L)
• Solve one-step word problems involving mass and volume
• Add, subtract, multiply, and divide with mass and volume measurements

Mastery Signs

Your child has mastered this standard when they can:

• Choose appropriate units and tools for measuring mass and volume
• Make reasonable estimates before measuring
• Measure accurately with standard tools
• Convert between related units (e.g., grams to kilograms)
• Solve multi-step problems involving mass and volume
• Apply measurement skills in real-world contexts like cooking or science
• Explain their measurement process and reasoning

Below Grade Level

For students who need additional support with basic measurement concepts.

Download Practice Worksheet

At Grade Level

For students who are working at the expected level for this standard.

Download Grade Level Worksheet

Above Grade Level

For students who are ready for more challenging measurement problems.

Download Challenge Worksheet