Experimental Design

Experimental Design Hypotheses

Objectives • Become proficient at writing problem statements, hypotheses, and experimental procedures. • Identify independent variable, dependent variables, and controls when exposed to a scientific experiment. • Describe the correct way to gather data in an experiment.

The Plan • You need your Super Volcano lab. • We will be taking some notes, going over some examples, and filling out our lab sheet. • Write/analyze problem statements. • Write hypotheses. What is the problem statement of our super volcano lab?

First Example • This first video is the basis of the myth tested by the mythbusters.

First Example • Now we’re going to watch a clip of the episode of Mythbusters in which they test the Lego myth. • Listen and write their for their problem statement(s). #1 #2

Problem Statements • What we’re the problem statements? • Does a lego ball this size require 5 million pieces? • Is a lego ball this size easily moved around? • Will a ball bounce off a car? Are these acceptable?

Problem Statements • A problem statement is a question statement that identifies what needs to be solved. Problem statements are formed as questions because they are identifying something that needs an answer. A problem statement should be specific so that anyone reading or hearing it knows exactly what needs to be measured to answer the question.

Words to Use and Avoid (for problem statements and hypotheses) • Words to use to help generate measurable data: • “higher number” • “increase in…population, rate, etc” • “decrease in…” • Words to avoid (will not generate measurable data): • “longer” • “better” • “faster” • “more effective” • “best” • general words that do not identify specifically what is being talked about, such as “it”

Hypothesis • What is a hypothesis? • A hypothesis statement is: • A proposed answer to a problem. • Based on observations. • Testable (must be able to measure what is being tested). • Do not define a hypothesis as: • An “educated guess” • An “if-then” statement

Hypotheses • If a hypothesis is a PROPOSED answer to a problem, you cannot be afraid to be incorrect. "It is very unnerving to be proven wrong, particularly when you are really right and the person who is really wrong is proving you wrong and proving himself, wrongly, right." -Lemony Snicket

Things That Have Been Wrong Science that has changed: • There are nine planets in our solar system.

Things That Have Been Wrong Science that has changed : • There are 109 elements.

Things That Have Been Wrong Science that has changed: • Maggots “arise” from decaying meat.

Things That Have Been Wrong • “Television won’t last. It’s a flash in the pan.” — Mary Somerville, pioneer of radio educational broadcasts, 1948.

Things That Have Been Wrong • “Heavier than air flying machines are impossible.” — New York Times, 1936 Hyperlink

Things That Have Been Wrong • "Everything that can be invented, has been invented." -- Charles H. Duell, Commissioner, U.S. Office of Patents, 1899.

Writing Hypothesis • NEVER USE, “I think” in a hypothesis. • The reader knows it’s you…you wrote it. Let’s look at the Same examples!

Objectives • Become proficient at writing problem statements, hypotheses, and experimental procedures. • Identify independent variable, dependent variables, and controls when exposed to a scientific experiment. • Describe the correct way to gather data in an experiment.

First Example – Writing a Hypothesis

Second Example – You Try! Let’s work on the worksheet!

First Example • Now we’re going to watch a clip of the episode of Mythbusters in which they test the Lego myth. • Listen and write their for their problem statement(s). #1 #2

Summary What three things must all problem statements be? Please write in a complete sentence! Homework Problem Statement and Hypothesis WS Closure and Summary

Experimental Design