I-N-D-E-P-E-N-D-E-N-T variables (and dependent and controls)

Objectives: SWBAT identify independent and

dependent variables in a controlled experiment.

Catalyst: Write a hypothesis to the following

question. Then describe how you would answer it. Would a tomato plant grow larger in natural light or artificial light?

Agenda

Catalyst Review How to work in Mr. Jhaveri’s lab Make mystery goo! What is an independent and dependent

variable? FOLDABLE Exit Question

Catalyst Review

Hypotheses! Is it educated? Is it testable?

How would you test it? What are you changing? What are you keeping the same?

Mystery goo! (30 minutes)

Once you have your procedure ready to go: Gather the materials you need.

Send logistics person to go get it. With your group, ANTICIPATE what will happen

Clean up: Beakers must be washed thoroughly. Place them upside down on the paper towels. Wipe down your desks and floors.

Mystery Goo Hypotheses

Let’s talk about the goo some more.

What would have happened if we added more water? How would you test it?

What would have happened if we added more corn starch? How would you test it?

Experimentation

Key Point #1: A proper experiment always has an

independent variable, dependent variable, and control group.

Scientists will change one thing and measure something else.If Mr. Jhaveri wears his basketball shoes, then he will score more points in a game.

Variables

Independent Variable: The thing that I change Basketball Shoes

Dependent variable: The thing that is measured Points

*Remember variables are always nouns!!

Good experiments…

ONLY CHANGE 1 THING!! You must keep everything else constant,

or your data may not be valid! Control Group: The group without the

independent variable. What was the control group in the

basketball experiment?

IMPORTANT!!!

Practice

Do older microwaves give off more radiation? What is the independent variable?

IV =

DV =

Microwave Age

Radiation

Practice

Are there more love bugs in the summer or the winter months? What is the dependent variable?

IV =

DV =

Season

Amount of love bugs

Practice

Students of different ages were given the same puzzle to assemble. The puzzle assembly time was measured. What was the dependent variable in this experiment?

IV =

DV =

Age

Puzzle Assembly Time

If there are more students, then there will be more school

buses.

IV =

DV =

Amount of students

Number of school buses

If the cost of beignets increases, then fewer will be sold.

What depends on what?

IV =

DV =

Cost of Beignets

Amount of Beignets sold

IV = Number of free agents

DV = Games Won

If the Saints sign more free agents, then they will win more games.

Foldables!

First flap: Real-life scenario in hypothesis form

Second Flap: Define and identify independent variable

Third Flap: Define and identify dependent variable

Fourth Flap: Define and identify control group

Exit Question

Identify the independent variable, dependent variable, and control group in the following scenario.

Dr. Ayaad believes that eating artichokes can decrease cholesterol. Dr. Ayaad recruited two sets of patients of equal age and health and she gave one group a normal diet and another an artichoke-filled diet. She then measured the patient’s cholesterol 2 weeks later.

COMPUTER TIME

One computer per 2 students.

Respect these computers. Always tie up cords before walking. Do not use excessive force when opening up the

computer. Be Patient!!!

Respect the time. If I see you on another website without permission,

you lose your computer privileges for the day and you will have an alternative assignment.

After you get your computer running… Go to this website: http://school.discoveryeducation.com/sci

encefaircentral/

On the brown tabs on the lower left, click virtual lab. Then, hit get started.

Click How Does Your Garden Grow Virtual Lab (Flash)