Prep Time: 10 minutes Lesson Time: 2 45-minute halves Age: 1st through 8th grades
Areas of Knowledge: science and writing
Background/objectives: Students will learn about each of the steps of the scientific method in an applied context
Materials: 5 stalks of celery, 5 cups, food coloring (red, yellow, green, blue) and water
1. Start by asking if anybody knows what an experiment is or why people perform experiments. If nobody knows, explain that experiments are tests we perform to answer a question. One example is testing out a new recipe.
2. Show the class the materials you have brought in. Ask them what they think they are going to do. Explain that all experiments start with a problem or question, and ask them what that question would be in this case.
3. Tell the class that after they think of a problem, scientists will do background research before doing anything else. Ask the kids to reiterate what they know about plants and how they drink water.
4. Explain what a hypothesis is and ask the class what they think is going to happen to each of the celery stalks when placed in the differently colored cups of water.
5. Perform the actual experiment. Pour water in each of the five cups. Put 2-3 drops of food coloring in four of the cups, and leave the fifth one without food coloring. Explain to the class that this cup is the control and that we use controls in all experiments so that we have something to compare the results to.
6. Set the cups aside until the next day. Ask the class to analyze what happened and whether their hypothesis was correct. Then explain that once they finish their experiments, scientists then try to report their conclusions in magazines or journals so that other people can learn about what they have discovered.
Have the children write down the parts of the scientific method as the experiment goes on, either in their journal or a worksheet
Tips and Tricks:
If nobody is participating or answering your questions, being able to put food coloring in the water is a good incentive, especially for the little kids. A big poster or dry erase board would also be useful so that the class can make a clearer definition of their hypothesis by writing it down.
How to implement for…
1-2: The most important thing for these kids to learn is what an experiment is and how important it is to follow the steps of the scientific method when performing an experiment. Learning the exact terms (hypothesis, analyze, etc) would probably be too hard for them.
3-4: Same thing as with first grade- focus on the process rather than the terms. Tell them the terms, but don’t worry about whether they remember it. These kids will also be better at paying attention than the 1st and 2nd graders.
5-6: These kids are old enough to remember all of the terms, so it would be helpful to quiz them to make sure they’re paying attention. You could have them write everything down or plan their own procedure. You can also do this activity with a more complex experiment.