# The Science Basics

## Independent and Dependent Variables

An independent variable is the variable in the experiment where you change something, while a dependent variable is the variable you use to take data in the experiment. The independent variable changes the results of the dependent variable. An example of an independent variable is I put bug spray on one arm, but not on the other. An example of a dependent variable is how many more bites I got on the arm that I didn't put bug spray on.

## Chosing a Good Hypothesis

A good hypothesis is the plausible explanation to an observation, or an question to a scientific experiment. In science a hypothesis always has to be able to be answered in a experiment. It must also include the dependent and independent variable. An example of a hypothesis is I think the arm without the bug spray is going to get more bug bites, because there's nothing there to protect it.

## Writing a Good CER

CER’s are a way to explain the experiment when you are done. C stands for claim. The Claim is where you make a statement to the problem, a response to the question, and an answer to the problem. An example of claim is the arm without any bug spray had more bites than the other arm. E stands for evidence. The evidence is where you provide data and facts that supports your claim. An example of evidence is I had eighteen bug bites on the arm that wasn't sprayed, while the arm that was sprayed had none. R stands for reasoning. The reasoning explains how the evidence is linked to the claim. It also explains why the experiment acted the way it did. An example of reasoning is because the bug sprayed arm repelled all of the insects from that arm they went to the other arm resulting in me getting eighteen bug bites on the arm that wasn't sprayed.