Big or Small Plants

Child pointing at a plant outside.

Measure plants growing outdoors. Which plant is bigger? Which plant is the smallest?

15 minutes


Get Ready

Materials you will need:

  • Bag (to carry materials outside)
  • Roll of string or yarn
  • Scissors
  • This Is the Way a Plant Grows: Lyrics PDF
  • Optional: Ruler
Materials PDF

Things to do before the activity:

  • Talk about different places in your neighborhood where you can find plants. Plants can grow in cracks in the sidewalk or buildings, community gardens, outdoor potted plants, grocery stores, apartment building grounds, and so on.
  • Together, sing and act out the song “This Is the Way a Plant Grows.”

A character with a speech bubble and rabbit with a thought bubble.

Plants are different sizes!

We can measure to find out how tall they are!


Step 1.

Before going outdoors, hold your hand next to your child’s hand. Point out that your hand is bigger, and your child’s hand is smaller.

Step 2.

Go outdoors and look for plants. You might find plants in the ground, in pots, or in a community garden. Talk about big and small plants you find.

  • What things do plants need to grow healthy and strong?
  • Notice the space between different plants. Does having space around plants help them grow big? Why do you think so?

Step 3.

Measure plant size. Measure several different plants or plant parts (such as leaves). Use string to measure. Hold one end of the string at the bottom of the plant to start measuring. Then stretch the string to the top to measure the whole plant. Cut the string when it reaches the top of the plant.

  • Why do we start measuring at the bottom of the plant?

Step 4.

Compare big and small plants. Lay the strings side by side to compare the sizes of the different plants.

  • Is this plant shorter or longer than the first plant we measured?
  • Point out the biggest plant. Point out the smallest.

Step 5.

Take a break if your child starts to lose interest. Sing and act out “This Is the Way a Plant Grows.” Make your “plant” wiggle and jiggle as it grows! Then go back to measuring.


Look at the string pieces together. Have your child line up the string pieces from smallest to biggest.

  • Were any of the plants we measured the same size? How do you know?
  • If we plant one seed in a sunny place and a second seed in a dark place, which one will probably grow bigger? Why do you think so?