Dependent and Independent variables explained Science

Learning Target: I can use embedded inquiry to conduct an experiment with an identified controlled and appropriate variables.

Did you know???? Did you know that if you can add 1 + 1, then you can learn today’s lesson about variables? Okay…..Here goes….. 1 + 1 = 2

That wasn’t bad at all was it? Since that was easy peasy, I guess you’re ready to begin with the lesson for the day. 2 + __ = ____ What does this problem equal???

You’re right!!!!! It depends! 2 + 2 = 4 2 + 4 = 6 2 + 12 = 14

Breakdown In every example, we changed one number…. ….and it affected the answer. 2 + 2 = 4 2 + 4 = 6 2 + 12 = 14 Therefore, the number depended on the number we changed.

I know….super simple right? Let’s practice. Fill in the blanks of the following 3 math problems to make the equations true. 10 + ____ =

I KNOW WHAT YOU’RE THINKING… What does this have to do with science?

Variables can be used in Math And Science. A variable is… something that can be changed. In our math problems, the numbers we changed were called variables. 2+2=4 A constant is… something that does not change. In our math problems, the number we decided not to change could be called a constant.

Science experiments use….. Independent variables – the one factor changed by the person doing the experiment. Dependent variables – the factor being measured in an experiment. Constants – all the factors that stay the same in an experiment.

In our math problems, we used dependent and independent variables ( The one number that we did change) 2 + 2 = 4 Dependent Variable (The number that depended on the independent variable) Constant (The one number that stayed the same)

How does this knowledge fit with science experiments?? Imagine you want to do an experiment to test what kind of plant food works the best. Miracle Gro, Jobe sticks, or the name brand. You would want to be sure that you changed ONLY what you are testing so that your results wouldn’t be messed up.

Types of Variables There are two main types of variables. Independent Variables-The variable that is changed by the scientist. The “I control” variable. Dependent Variables-The variable that might change because of what the scientist changes- What is being measure.

Remember…. Your hypothesis can help to tell you what your variables are. Example If I stay up all night playing video games, I might be tired and have trouble focusing during school. Independent Variable- Staying up playing video games Dependent Variable- focusing during school

Lets Practice!!! Use this hypothesis to identify the independent and dependent variables. If I leave the lights on all day, then my electric bill will be expensive. Independent Variable________________________________________ Dependent Variable__________________________________________

Practice!!! If I brush my cat more, then there will be less fur on my furniture. Independent Variables_____________________________________ Dependent Variables_______________________________________

A little More Practice… Elizabeth wanted to test if temperature affected how fast milk goes bad and curdles. She left milk in a room temperature closet, a fridge, and a oven that was turned on low heat. She then measured how rotten the milk was after 10 days. ​ ​ IV: ____________________________________​ DV: ____________________________________​

Our Experiment A B C Constant water, soil, light, daisy seed Independent Variable Miracle Grow Jobe Sticks Name Brand Dependent Variable Plant Growth (Most) Plant Growth (Good) Plant Growth (Little)

Our Constants and Variables The type and amount of dirt (same). The amount and timing of watering (same). The type and amount of light (same). Independent variable: The brand of plant food testing. (Miracle Gro, Jobes Stick, name brand) The amount of plant food given (same). Dependent variable: The health and growth of the plants. + =

Here’s how it works Constant Independent Dependent Variable Variable Same types and amounts of: water, sunlight, and soil Different Plant Foods Tested Health and growth of plant

Now… For any experiment, you should be able to identify: constants independent variables dependent variables Just by thinking… 1+1=2 OR Constants + Independent Variable = Dependent Variable