Science Fair - Experimental Design I

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Objective

SWBAT design, conduct & analyze an experiment using only items supplied

Big Idea

Designing, conducting & analyzing an experiment takes practice time for success.

The Need for the Lesson

Science Fair requires students to design, conduct and analyze an experiment. Sometimes students just do not know where to start. Practicing experimental design in class while collaborating with their peers helps students develop the confidence they need to tackle the much larger individual science fair projects. 

Investigation Preparation & Summary

10 minutes

Science fair is not an easy task for students especially if they have limited experience designing and testing their own experiments. This lessons is designed to give an opportunity to practice designing their own experiment with a partner so they are prepared to tackle the science fair on their own. Students begin by asking a question that can be answered using the materials provided, (SP1 - Asking questions)

Students will be give a document to help them begin planning their experiment. The overview includes all the elements need to begin their experiment. For this lesson students are not expected to write out detailed procedures. They will work on that process in the Science Fair - Write-It, Do-It lesson. (SP3 - Planning and carrying out investigations)

The data collected will be measured using meters and angles and students will calculate and graph averages of multiple tests. Students will learn that when creating a table, the independent variable should be listed first, then the dependent variable. (SP5Using mathematics and computational thinking)

Data collected in a table is a good way for students to begin to see a pattern. The graph of the average distance collected will help students see patterns in their data (SP4Analyzing and interpreting data)

After students have graphed their data, they should be able to describe the data and what it tells them. A cause and effect relationship should be noticed by students. (SP6 - Constructing explanations) (SP7 - Engaging in argument from evidence) (SP8Obtaining, evaluating, and communicating information)

A complete materials list can be found in the resources section.

This lesson was inspired by the North Carolina Science Olympiad Coaches Clinic document prepared by Michael D. Huberty. You can find the document in is entirety here

Students in Action

90 minutes

To prepare for the upcoming science fair, we will practice designing experiments. For the actual science fair you will of course be working independently. This is your opportunity to practice designing and implementing an experiment working with a partner.

Today you will design an experiment using only the materials provided. 

The materials available are 5 wooden craft sticks, a writing instrument which makes good fulcrum FYI, 5 rubber bands, a calculator, 5 gummy bears, a timer, meter sticks and your science journal.

There are a variety of rubber bands to select from for this experiment.

With a partner you will need to ask a question, identify experimental controls, independent, dependent variables and a hypothesis.

What kind of question should you ask? A question that does not have a simple yes or no answer.

Once you and your partner have decided upon your experiment design a data collection table. The first thing listed in your table should be your independent variable. What is the independent variable? What you should change in an experiment. The next item listed should be the dependent variable. What is the dependent variable? What you should measure in an experiment.

When you write your hypothesis please use the following format. If... then... because... where you state in the if part of the sentence what you are changing, in the then part of the sentence tell us what you think will happen and in the because part of the sentence give us a reason you think your hypothesis is correct.

To help you with the process, you will use Writing an Overview of Your Experiment as a guide to be sure you have all of the required information. You will be writing your overview in your science journal.

You will want to have this experimental design write-up in your journal to reference later when you design your own experiment for science fair.

The students quickly determine that they will be launching the gummy bears into space. The wooden sticks and rubber bands become catapults and slingshots. 

Students build and test their launching devices.

There are two questions that student groups are asking. One is does the angle of launch matter and the other is does the distance the rubber band is pulled back matter. I do not expect students to do additional research for this experimental design activity. This lesson is designed to focus on asking a question and designing an experiment. 

For students who decide to test the angle of launch, I share a short video about how a long jumper maximizes his distance by the angle of his jump. The video is part of the NBC Learn - Science of the Summer Olympics website found here. The short video helps students research what they already intuitively know - that the angle does matter when distance is the goal. A few of my students have an aha moment as they can now relate to what the track and field coach has been trying to tell them to do to improve their own long jump.

In this short video, watch students as they measure both the angle of the launch and check to make sure that the distance the the rubber band is pulled back remains constant.