Family Math Activity: Make a Balance Scale

Children are naturally curious about measurement and enjoy comparing the objects in their environment. Which dog is the biggest? Which package is the heaviest? Which family member is the tallest? Each of these questions can be solved using the important early math concept of measurement. When we measure, we use numbers to describe the world around us more accurately than with our senses alone.

In this activity, you and your child will make a balance scale to compare the weight of different objects, use nonstandard measurement and get measurement games your child can play again and again.

Paper cups work great for this activity because they are easy to pierce. Children can also use markers or stickers to decorate the paper cups! Plastic berry cartons with holes in the sides are also easy to use.

Learning Goals

In this activity, your child will:

• Compare the weight of different objects using a measurement tool.
• Make observations and predictions about weight and balance.
• Use nonstandard measurement units to describe how much the object weighs.

Vocabulary

• Balance scale: A set of scales that balances when both sides weigh the same.
• Measurement: Using numbers to describe an attribute of something, such as length, weight, volume or number.
• Nonstandard measurement: Using everyday objects to measure an object instead of using a tool made for measurements, like a ruler, yardstick or scale.

Materials

• Plastic or wire hanger with notches
• Two equal-sized paper cups, plastic berry cartons, or other containers
• One hole punch (optional)
• Pencil (optional)
• Yarn
• Scissors

Step-by-Step Instructions

1. Use a sharpened pencil to draw two marks on opposite sides of the cup that are about 1 inch (or the width of two fingers) away from the top. Use a hole punch to create two holes at the marks. If you don't have a hole punch, you can use the sharpened pencil (adults only) to pierce through the marks to create the two holes. Repeat this step for both cups. If you are using plastic berry cartons, your holes are already there!

2. Cut two pieces of yarn that are each approximately 1 foot long. After you cut the first piece of yarn, your child can help you by cutting the second piece of yarn to match the length.

3. Thread the first piece of yarn through a hole in one cup and tie one end over the top. Then, take the other end and tie it to the other hole. Your cup should now look like a bucket with a long yarn handle. Repeat for the second cup. Have your child hang the two yarn-cup creations from the notches at opposite ends of the hanger. Your balance scale is ready!

4. Find a place to hang your balance scale. You can use a doorknob, dresser handle, or cabinet handle within your child's reach. If the hanger doesn't look even, you may need to experiment with the placement or weight of the cups you used.

If you're playing with older kids, have them take the activity a little further by balancing the scale off a table to reduce the friction of the cups against the door. To do this, have them place a pencil at the edge of the table — eraser-end out — and put a heavy book on it. Then, they can place the hanger on top of the edge of the pencil.

Inspired by Go Science Kids' DIY Balance Scales for Toddlers and Preschoolers.

Ways to Play

Encourage your child to explore the balance scale. Have them find and place different objects in the two cups. First, have them guess which object is heaviest before placing it in the cup. What happens to the cup holding the object that seems heaviest? It moves down! Repeat this multiple times with different toys and everyday objects until your child is familiar with this pattern — the heavier object moves downward while the lighter object moves upward.

• Can your child find two objects that weigh the same? Encourage them to search around the house for two objects that will make the scale balance when placed in the cups. They will need to try many different objects on the balance scale and then compare the cups' heights until they are at the same height.
• Describe how much an object weighs using nonstandard measurement. When using nonstandard measurement, we try to measure with something that's not a traditional measurement tool, like a ruler or digital scale.
  • Begin by modeling for your child how to describe the weight of their favorite small toy using equal-sized marbles (if you don't have marbles, any objects with the same weight, like quarters, will work).
  • Continue placing marbles in the cup and count the number of marbles together until the scale is balanced.
  • Write down how many marbles are equal to the weight of each toy you weigh.
  • Make this a game by guessing how many marbles different toys weigh before measuring with the balance scale. After finding the weight of different toys, compare them by asking your child which was the heaviest!
  • For older children, ask them to find the difference between the heaviest and lightest toy using a subtraction problem: The number of marbles of the heaviest object minus the lightest object equals the difference between the two weights.

Keep the Conversation Going

Watch

Learn About Measurements Using a Homemade Scale

• Create a different kind of scale to demonstrate to your child that they can use different tools to measure the attribute of weight. In this PBS SoCal measurement activity, you and your child will use a ruler, marker, cups and tape to create a balance scale that works just like a seesaw!
• Continue to explore the physics of balance withthis balance sculpture activity. You will need a plastic bottle with a lid, a large carrot, a knife to cut the carrot, skewers and food items like fruit. You can find the full instructions on the Medium website (plus some cool facts about mass for older kids to read), but here's the gist.
  • Cut a portion from a large carrot and slice it down the middle, so it resembles a semicircle.
  • Cut a small length of the skewer and push it into the center.
  • Push two regular skewers into the bottom of the carrot diagonally, so they face each other.
  • Ask your child to find and place two equally sized food items onto the ends of the long skewers.
  • Place the short skewer on top of a plastic bottle to see if it will balance!
  • Have your child place more food items onto the skewers, such as grapes, strawberries or pineapple chunks, always adding to both skewers equally, so the sculpture stays balanced.
  • Continue to add new skewers, two at a time, and see how large you can make the sculpture while keeping it balanced!

Book Suggestions

"Balancing Act" by Ellen Stoll Walsh (Ages 2-6)

Explore the concepts of balance and weight with mice on a teeter-totter in this lovely board book. Use the storybook guide by DREMEto help you talk about the math in the book while reading together.

“Lia y Luís: ¿Quién Tiene Más? / Lia & Luis: Who Has More?” by Ana Crespo (Ages 3-5)

When children compare amounts, they build their understanding of quantity, weight and other measurable features. In this warm picture book featuring Brazilian American siblings, your child will explore the math of comparing and measuring. Use the storybook guide by DREME to help you talk about math while you read together.

You can also find out more about what inspired Ana Crespo to write the book and how she chose the main characters.

Corresponding Standards

California Preschool Learning Foundations
Math- Measurement

• 1.0: Children expand their understanding of comparing, ordering, and measuring objects.
• 1.1 Compare two objects by length, weight, or capacity directly or indirectly.

Science- Observation and Investigation

• 1.3 Identify and use a greater variety of observation and measurement tools. May spontaneously use an appropriate tool, though may still need adult support.

Head Start Early Learning Outcomes Framework

• Goal P-MATH 8. Child measures objects by their various attributes using standard and nonstandard measurement. Uses differences in attributes to make comparisons.
• Goal P-SCI 3. Child compares and categorizes observable phenomena.

Common Core State Standards - Kindergarten

• Describe measurable attributes of objects, such as length or weight. Describe several measurable attributes of a single object. (CSS.MATH.CONTENT.K.MD.A.1)
• Directly compare two objects with a measurable attribute in common to see which object has "more of "/"less of" the attribute and describe the difference. For example, directly compare the heights of two children and describe one child as taller/shorter. (CCSS.MATH.CONTENT.K.MD.A.2)