Scientific Method study guide

There will be a test on the scientific method on Friday, March 7. For the test, students will need to understand the parts of an experiment. Here's a study guide for the vocabulary terms.

independent variable = the variable that is purposely changed by the scientist in order to see if the dependent variable changes with the independent variable; you can also think of this as the difference in your groups. 

dependent variable = the variable observed and/or measured during the experiment to find out if it changes with the independent variable 

controlled variables = all the things that could change but the scientist keeps the same to prevent them from interfering with the experiment 

hypothesis = a prediction of what you will find in your experiment; a predicted answer to your scientific question; a hypothesis is usually stated as an if/then statement.
Important detail: A scientific hypothesis must be testable.

In our class experiment, we had the question, "Do 7th grade DRMS boys have better hand-eye coordination for throwing than 7th grade DRMS girls?"

Our hypothesis was, "If I compare the accuracy of 7^th grade DRMS males and females at throwing tennis balls into a trash can, then it will be found that males are more accurate than females."

Our independent variable was the gender of the people--boys vs girls. That's what we changed about the groups.

Our dependent variable was the number of baskets scored by each person. That is what we measured to see if it changed with the groups.

Our controlled variables included everyone using the same tennis balls, standing the same distance away, throwing at the same trash can, in the same room, having the same number of tries, etc.

Remember that the independent and dependent variables will be in the hypothesis. The "if" part contains the independent variable, and the "then" part contains the dependent variable. In our experiment, the "if" was comparing boys and girls, and the "then" was the number of baskets scored per person. You should be able to determine the independent and dependent variables by looking at the hypothesis.

Here's another practice problem:

Billy Bob wanted to know if organic pesticide works better than artificial pesticide at preventing oleander caterpillars from attacking his oleander plant. After reading about other people's experiments, he learned that most researchers have found organic pesticides are less effective. So, he developed this hypothesis:
"If organic pesticides and artificial pesticides are compared in their ability to prevent oleander caterpillars from attacking oleander plants, then it will be found that oleander plants treated with organic pesticides will have more caterpillars than oleander plants treated with artificial pesticides."

1) What is the independent variable?
2) What is the dependent variable?
3) What are three controlled variables needed for this experiment?

Chapter 4

We're starting to work on Chapter 4: Cell Reproduction. In this chapter, students will learn about mitosis and meiosis, as well as DNA. If students want to review any of the information at home, they can use this link for chapter 4 from the textbook.

To review past information, here are links for chapter 3, chapter 2 and chapter 1 from the textbook.

AR extra credit

Here's an extra credit opportunity that will continue from now until March 21. Read any AR book from the 500-section (sciences) in the library, and then pass the AR test with at least an 80%. Your extra credit will be five times the number of AR points for the book. So, if the book is worth 4 AR points, you will earn 20 extra credit points (4 AR points times 5 = 20).

You can read any book from the 500-section in the library. But, you also read a biography on a scientist. Just make sure the biography is of a scientist. Example of scientists our library has biographies about include Ben Franklin, Marie Curie, Jane Goodall, Isaac Newton, Lise Meitner, and George Washington Carver.

In order to get the extra credit points, you must:
a) score at least 80% on the AR test.
b) tell me the name of the book, the author, your AR test score, and your Reading teacher (so I know which group to look at to verify your school and points). 

You can read as many books as you want between now and March 21. But, March 21 is the last day to give me the information for your extra credit.

This extra credit assignment gives you an opportunity to earn points in science while also completing the independent reading homework you have in reading class and earning AR points for reading.

Summary paragraphs

At the end of our lesson about Yellow Fever, each student was to write a paragraph explaining the importance of Dr. Walter Reed. Students recently learned the new format for writing summary paragraphs. They need to have a main idea, at least three detail sentences, a writing device (simile or metaphor), and a conclusion. The parts of the paragraph are to be labeled, and you can see the labels circled in the example shown below. After the paragraph example, I've also shown some of the notes the student used to write the paragraph.

 

extra credit due Wed., Jan 15

Here are two chances for extra credit. Each question is worth 10 points if answered correctly. So, you can earn up to 80 assignment points. These are due on Wed., Jan 15. 

Read the article, "Settling the Americas," and then answer these questions:
1) What was the old hypothesis about when humans first started moving into the Americas?
2) What is the new hypothesis for when humans first started moving into the Americas?
3) What groups of people were compared in this investigation?
4) What changes in the environment made it possible for people to move into the Americas?
5) Why is it unlikely that archaeologists will find artifacts left behind by the first settlers in the Americas?

Read the article, "Fun Veggie Names Ups Kid Intake," and answer these questions:
6) What was the independent variable?
7) What was the dependent variable?
8) What was the conclusion?

How to create a dichotomous key

This week, students have been learning about dichotomous keys. Their test will be to create a dichotomous key, which they have practiced a few times. This video provides a very good method for creating a dichotomous key.

If you want to practice making a dichotomous key, you can try it using these emoticons. I've given you names for each face. Create a key that would allow someone else to match a face with a name.

Chapter 1

Here's a link to a PDF version of chapter 1 from our textbook.