Process Skills 4. Hypothesis

4. A HYPOTHESIS is an educated guess as to the results of an experiment. One way to write a hypothesis is to use the “If…then…” statement.

A. A VARIABLE is something that can change (vary) in an experiment A. A VARIABLE is something that can change (vary) in an experiment. Most experiments have two kinds of variables: manipulated/independent and dependent/responding.

B. IF: this is the variable you change on purpose or test in an experiment. Experiments should only have one variable you change on purpose. It is called the MANIPULATIVE OR INDEPENDENT variable and is graphed on the x-axis. MIX

C. THEN: this is what you observe or measure in your experiment C. THEN: this is what you observe or measure in your experiment. It occurs because of whatever you changed on purpose in the experiment. It is called the DEPENDENT OR RESPONDING variable and is graphed on the y-axis. DRY

D. IF (I change this one thing on purpose)…THEN (this is the result I will observe). IF (MV)….THEN (RV).

Prediction Inference Observation 3. The airplane will land at the airport on time. 2. The airplane flew from the airport. 1. The airplane is silver and blue. 4. The boy will make a 100 on his test. 6. The boy has a blank look on his face because he did not study for the test. 5. The boy is holding a pencil. 9. The girl will probably play the CD after supper. 8. The girl paid over $10 for the CD. 7. The girl has a CD in her hand. 10. The butterfly might fly away to Mexico. 12. The butterfly is orange and black. 11. The butterfly came out of a cocoon. 5. The boy is holding a pencil. 9. The girl will probably play the CD after supper. 1. The airplane is silver and blue. 6. The boy has a blank look on his face because he did not study for the test. 10. The butterfly might fly away to Mexico. 2. The airplane flew from the airport. 11. The butterfly came out of a cocoon. 3. The airplane will land at the airport on time. 7. The girl has a CD in her hand. 12. The butterfly is orange and black. 4. The boy will make a 100 on his test. 8. The girl paid over $10 for the CD.

Cookie Monster Sheet for Notebook Cookie Monster has created a brand new cookie that he thinks will help little monsters run faster through a maze. He splits the monsters into two groups with 5 monsters in each group. Group A will get the regular cookie and Group B will get the special cookie. He sends both groups into the maze and times each monster individually. Then he gives each monster the cookie. They eat it and run through the maze again. Cookie Monster writes down the second time as well. Both groups are told that they are getting the special cookie but only Group B is really eating it. Here are the results of the time trials:

GROUP A: GROUP B: Time Before Cookie Time After 10 sec. 15 sec. Time After Cookie 15 sec. 12 sec. 24 sec. 20 sec. 17 sec. 14 sec. 10 sec. 11 sec. 7 sec.

Cookie Monster Questions 1. Which people are in the control group? Group 2. What is the manipulated variable? 3. What is his hypothesis?   4. What should Cookie Monster’s conclusion be?

Beans, Beans, Beans Without looking, reach into the bag and take out a sample of ten (10) beans. Record the number of each bean under the column labeled as SAMPLE 1. Return the beans to the bag and mix them with the other beans. Repeat the procedure until you have completed four samples. From the results on the first four samples, predict what you think you will draw for the fifth sample. Write your prediction in that column. Sample ten (10) beans and record the results under SAMPLE 5. Beans Sample 1 Sample 2 Sample 3 Sample 4 Prediction Sample 5 Red   Green Speckled White

Day 2 Hypothesis

Linus Read each experiment and answer the questions about the variables and scientific method: Linus and the Dirty Blanket Linus discovered that his blanket was getting dirty and he wanted to clean it. Lucy suggested buying Peanuts Laundry Detergent and using it on the blanket. Charlie Brown suggested using Schulz Laundry Detergent to clean the blanket. As Linus had several blankets and all of them were equally dirty, he decided to wash one in plain water, one in Peanuts Laundry Detergent and one in Schulz Laundry Detergent. He repeated the experiment several times. After he had completed the investigation, it looked like the blanket washed in Schulz Laundry Detergent was the cleanest.

1. What was the problem that Linus wanted to investigate. 2  1. What was the problem that Linus wanted to investigate?   2. What is his manipulated variable?   3. What will Linus look at to see if the detergent works? So what will be his responding variable?   4. What should Linus’ conclusion be?

Name _______________ How Many Drops of Water Can a Penny. Hold Name _______________ How Many Drops of Water Can a Penny Hold? (investigating variables) Materials you will need include: Eye dropper or pipette cup of water penny paper towel(s) Procedure: Using the materials above, what would you do to determine how many drops of water would fit on the surface of your penny? Describe what you would do? Prediction: Before you begin to carry out your experiment, predict how many drops you think you can place on the penny without the water flowing over. I predict the penny will hold ____ drops of

Experiment: Carry out what you described above in the procedure Experiment: Carry out what you described above in the procedure. You will work independently or with a partner. Record the number of drops your penny held in the table below and then find the average of drops. Trial #1 __________ Trial #2 ____________ Trial #3 ______________ Add the three numbers together and divide by three to find the average:

Analysis: Were you surprised at the results? Why or why not? As you were conducting the experiment, was there anything about the way that you worked that was different from the way someone else worked? [For example, did you hold your dropper a different way from your neighbor?] If so, list some of the differences below: These differences are called variables because they change or vary from one person to another. List at least three common variables that could affect the results of this experiment. The first one is complete for you. Variable #1: how high you hold your hand Variable #2: ___________________________________________________ Variable #3: ___________________________________________________