1. Catalyst – January 7+6, 2011 Daneel is a college chemistry student. He was told by his professor to research the fuel efficiency (for example: miles per gallon) of various types of gasolines. 1. What is one question you would want to answer by doing research on this topic? 2. Briefly, describe a method/procedure that Daneel could perform to learn something about the fuel efficiency of various gasolines.

2. Todays Agenda Catalyst Variables Notes and Practice Time I-N-D-E-P-E-N-D-E-N-T! DEPENDENT CONSTANTS Exit Question

3. Todays Objectives SWBAT identify independent, dependent, and constant variables in a scientific experiment.

4. Experimentation Key Point #1: A proper experiment always has an independent variable and dependent variable. The purpose of an experiment is to test how changing ONE THING affects something else.

5. Variables Independent Variable: what causes the change we are measuring (acts independently) Dependent variable: what gets changed (depends on other things) Remember!!!! Variables are always CATEGORIES of things: time, amount, frequency, size, type Variables are NEVER specific things!!!

6. Demo http://www.unitedstreaming.com/ videos/dsc/externalApplications/ virtual_labs-es/Plants/index.html http://www.unitedstreaming.com/ videos/dsc/externalApplications/ virtual_labs-es/Plants/index.html

7. Teacher Models Scientists have discovered something shocking: if you eat a lot of hamburgers, then you will gain fat. What is the independent variable? A. Eat a lot of hamburgers B. Type of hamburger you eat (McDonalds, Wendys, Burger King, etc.) C. Amount of hamburgers you eat D. How much weight you gain

8. Teacher Models Well-rested students learn more in school. So, Ms. Stroh believes that starting school later would increase test scores. What is the dependent variable? A. Starting school later B. Well-rested students C. Time that school starts D. Test scores

9. NEW PROCEDURE! WHITEBOARDS!

10. Whiteboard Practice When Ms. Stroh says GO! Send one member of your group to get whiteboards, erasers, and markers for everyone (back lab bench) Hurry! Remember, we want to stay under 3 minutes of transition time!

11. Whiteboards 1 Ms. Stroh believes that the more you study, the better grades youll earn. What is the independent variable? A. Studying more B. Amount of time you study C. Grade earned D. Type of test

12. Whiteboards 2 Shanel is always cold in class. She hypothesizes that if she wears many layers of clothing to school, then she will be warmer. What is the dependent variable? A. Number of layers Shanel wears B. How warm Shanel is C. Temperature of the room D. Shanel will be warmer

13. Whiteboards 3 Ms. Strohs students want to test how easily bought off she is. Students who give her an apple get a C. Students who give her candy get an A. What is the independent variable? A. Type of food given to Ms. Stroh B. Apples and candy C. A on the report card D. Report card

14. Whiteboards 4 Tashica hates cooking, but loves listening to music. She believes that if she listens to music while cooking, then she will cook more often. What is the dependent variable? A. She will cook more often B. Listens to music while cooking C. Frequency that Tashica cooks D. What Tashica listens to

15. If youre having trouble… 4 minutes 26 mg of baking soda Lifting weights every day Medium t-shirts Bullfrog 16 candles Never gets sick Time to get dressed Amount of baking soda Frequency of lifting weights Size of t-shirts Type of frog Number of candles Degree of health WRONGRIGHT

16. Review Ms. Stroh believes that the more you study, the better grades youll earn. What is the independent variable? A. Studying more B. Amount of time you study C. Grade earned D. Type of test

17. Review Shanel is always cold in class. She hypothesizes that if she wears many layers of clothing to school, then she will be warmer. What is the dependent variable? A. Number of layers Shanel wears B. How warm Shanel is C. Temperature of the room D. Shanel will be warmer

18. Review Ms. Strohs students want to test how easily bought off she is. Students who give her an apple get a C. Students who give her candy get an A. What is the independent variable? A. Type of food given to Ms. Stroh B. Apples and candy C. A on the report card D. Report card

19. Review Tashica hates cooking, but loves listening to music. She believes that if she listens to music while cooking, then she will cook more often. What is the dependent variable? A. She will cook more often B. Listens to music while cooking C. Frequency that Tashica cooks D. What Tashica listens to

20. Guided Practice Worksheet 10 minutes to complete 3 minutes to compare answers KEEP THIS to help you with homework tonight

21. Constants Key Point #2: Everything but the independent and dependent variable must be kept constant. Constant: variable we keep the same If many different things change at once, we dont know what causes the change!

22. Example Lets say we want to design an experiment to determine what causes the Hornets to win games.

23. Number of games that Hornets win

24. Try this one! Answer in notes… Travie McCoy hypothesizes that if he write more songs about being rich, then he will sell more CDs because his listeners also want to be rich. What is the IV? What is the DV? What are the constants? Remember, variables are CATEGORIES.

25. If Travie write more songs about being rich, then he will sell more CDs because his listeners also want to be rich. IV Number of songs about being rich How often Travie sings about being rich Amount of times Travie sings about money DV Number of CDs Travie sells How many CDs Travie sells Constant Amount of money CDs cost Number of tracks on each CD How good each CD is

26. Practice You want to know when in the year there are the most love bugs. Every night, you record how many love bugs you find outside. IV = DV = Constant = Time of year (season/month) Amount of fireflies

27. Practice Maria needs to run a 6 minute mile to pass PE. She believes that if she runs every day, then she will be able to run faster. IV = DV = Constant = Frequency that Maria runs Mile time

28. Practice Students of different genders were given the same puzzle to assemble. The puzzle assembly time was measured. IV = DV = Constant = Type of gender Time to assemble puzzle

29. If there are more students, then there will be more school bus drivers. IV = DV = Constant = Amount of students Number of school bus drivers

30. If the amount of sugar used on beignets decreases, then less beignets will be sold. What depends on what? IV = DV = Constant = Amount of sugar used Number of beignets sold

31. IV = Number of games won DV = Number of players attracted Constant = If the Saints win more games, then they will attract more big name players.

32. Conclusion A proper experiment always has an independent variable and dependent variable. Everything but the independent and dependent variable must be kept constant. Independent Variable: what causes the change we are measuring Dependent variable: what gets changed Constant: variable we keep the same

33. Exit Question Lets say you want to figure out if drinking milk actually makes you taller. So you drink a glass of milk every day, and record your height every day. 1. What is the independent variable? 2. What is the dependent variable? 3. What are at least two constants? HW: IV, DV, Constants Worksheet!