Eddie’s Flower Experiment: Working Through the
Scientific Method

The scientific method helps you find answers to your questions about the world. It starts with a question and your answer to the question based on your observations. This “answer” is called your hypothesis. The next step is to test your hypothesis by creating experiments that can be repeated by other people in other places. If your experiment is repeated many times with the same results and conclusions, this information becomes part of the scientific knowledge we have about the world.
Steps to the Scientific Method

Read the following story and highlight any key information. You will use this story to practice using the scientific method.

Eddie gives his mother a bunch of roses for Mother’s Day. She fills a vase with water, trims the ends of the flower stems, and arranges the roses in the vase. Then she remembers that she heard from a friend that putting an ammonia in the water helps the flowers stay fresh longer. She goes to the cleaning cabinet to look for ammonia.

Eddie’s sister Kela comes into the kitchen and sees the flowers. She said she heard putting a few drops of bleach in the water helps keep the flowers fresh. She thinks it is because the bleach kills the bacteria in the water.

Eddie thinks it seems strange that household cleaners would be better than plain water. He has observed his science teacher watering plants with plain water and those plants appear to be healthy. He asks his mother if they can do an experiment to find out whether the ammonia or bleach will make the flowers last longer. She thinks it is a good idea and finds some smaller vases to hold the flowers.

Now, answer the following questions about the process they used to reach their conclusion.

Make observations or research something
What observation did Eddie make in his science class?

Ask a question or state a problem (What effect does ___ have on ___?)
b. What testable question does Eddie want to answer during the experiment?

State a hypothesis- Using “If….then….”
c. What hypothesis would Eddie’s mother make based on the information she heard from a friend?

d. What hypothesis would Kela make?

e. What hypothesis would Eddie make?

Test the hypothesis with an experiment
Eddie, Kela, and their mother divide the flowers into three bunches of four flowers each. They mix the flowers so the bunches are as identical as possible. They put water in the vases. Into one vase, they add 10 milliliters of ammonia, mix the water, and add the flowers. Into another vase, they add 10 milliliters of bleach, mix the water, and add the flowers. The flowers are put into plain water in the third vase. The three vases are placed near a window on the kitchen counter. They decide to change the water and cleaning products each day. Each day they will also compare the condition of the flowers by counting the number of petals lost.

f. What should be the same for all three vases (control variables)?
Now, answer the following questions about the process they used to reach their conclusion.

Make observations or research something
What observation did Eddie make in his science class?

Ask a question or state a problem (What effect does ___ have on ___?)
b. What testable question does Eddie want to answer during the experiment?

State a hypothesis- Using “If….then….”
c. What hypothesis would Eddie’s mother make based on the information she heard from a friend?

d. What hypothesis would Kela make?

e. What hypothesis would Eddie make?

Test the hypothesis with an experiment
Eddie, Kela, and their mother divide the flowers into three bunches of four flowers each. They mix the flowers so the bunches are as identical as possible. They put water in the vases. Into one vase, they add 10 milliliters of ammonia, mix the water, and add the flowers. Into another vase, they add 10 milliliters of bleach, mix the water, and add the flowers. The flowers are put into plain water in the third vase. The three vases are placed near a window on the kitchen counter. They decide to change the water and cleaning products each day. Each day they will also compare the condition of the flowers by counting the number of petals lost.

f. What should be the same for all three vases (control variables)?