Designing a Fair Test

In this unit, students explore why scientists and other professionals use models when trying to solve problems or create solutions. Students make their own model of a watershed using a landform map and answer a writing prompt about building a model before making a town decision to build a dam.

Activities

Scene: Debate after the Race

This scene introduces the idea of a fair test through a discussion about an unfair running contest. The characters discuss why it was unfair and uncover the problems that occur when the principles of a fair test are not included. Most students have had some exposure to competitions and contests that try to determine the “best” at some skill. This unit's scene demonstrates a group of students struggling to understand what makes a contest fair.

Duration: Approximately 50 minutes

Lesson: Elements of a Fair Test

This lesson reviews the science practices of controlling variables, conducting multiple trials, and ensuring objective measurements.

Duration: Approximately 50 minutes

Lab: Straw Flyer Trials

Student groups will make straw flyers and design a contest that considers the principles of fair tests. Each group will then conduct the contest and record the data. Groups will then report the results of their competition. Afterwards, the class will evaluate the competition in a class discussion.

Duration: Approximately 120 minutes

Reading: Fair Trials in Teen Court

Students read and discuss an article about a teen court program in Florida and think about how fair trials in the legal system might relate to fair tests in science.

Duration: Approximately 30 minutes

Reading: Olympic Rules on Swim Suits

Student relate a real-life situation to the principles of fair testing including objective measurements, controlling variables, and multiple trials. In this passage, students read about the controversy during the 2008 Olympics where swimmers were setting new records due to an unfair advantage from new bathing suits.

Duration: Approximately 25 minutes

Writing: New Nation's Olympic Trials

Students write a response to a hypothetical situation to demonstrate their knowledge of the principles of fair tests.

Duration: Approximately 35 minutes

Teacher Tune-ups

• In science, what do we mean by fair?

Student View of Visuals and Activities

Some teachers prefer to have students view the slides and other visual assets in this unit directly instead of projecting them in class. Below is a web page to share with students with links to the same items within in the teacher lesson plans, but without the explanatory text for the teacher.

 

• Student Links to Unit T4 Slides and Other Visuals

Original SciGen Unit

This unit has been adapted from "6.4 Is that really a fair test?" in the Word Generation program led by Catherine Snow (Harvard University) through a SERP collaboration with the Boston Public Schools and other districts in Massachusetts and Maryland.

PDFs of that earlier unit's teacher and student editions are available at the Science Generation Download Center.

fair

adjective – treating everyone in a way that is right or equal

In science, something is fair when variables are controlled so that they do not affect a test result.

The teacher argued that the test was fair because every student got the same questions and had the same amount of time to take it.

trial

noun – a test or experiment

In law, a trial is when lawyers from different sides present evidence to figure out if someone is guilty.

In science, a trial is a test that is repeated as part of an experiment.

The factory tested the safety of its new line of cars by driving them in trials in the rain, in the snow, up hills, and in the fog.

variable

noun – something that can change in different situations

Related form: vary (verb)

In science, a variable is something that, if it changes, can lead to different results in a trial or experiment.

Some of the variables that can affect how well a football player performs are how much he practices, how well he eats, and how much he works out.

objective

adjective – deciding something based only on the facts, not how you feel about someone or something

In science, something is objective if it can be proved based on facts.

To decide who wins an athletic contest, there should be an objective measure.

process

noun – a series of steps or actions to get a result

In science, part of the scientific process is to repeat trials and experiments to make sure that a result is correct.

The process of testing the powder for toxins was complicated and dangerous.

controlling (control)

verb – making sure everything works the way you want it to

In science, controlling for different things means making sure they stay the same in the experiment so you’re only measuring the thing you want to measure.

Since the paper airplane contest was held outside on a breezy day, controlling the variable of wind was difficult.