SCIENTIFIC METHOD

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Day 1 Notes: SCIENTIFIC METHOD

(It’s a way of thinking)

STEP

_________________

KEY THINGS TO REMEMBER

MUST BE TESTABLE

Be Specific

plant growth?

Practice a. Which fertilizer will lead to the most plant b. Which gum is the best?

(Best what???) c. Why doesn’t my crush like me?

_________________

GATHER INFORMATION

Research

Observations (_____________)

Inference

Self-OBSERVATION: _______________________

________________________________________

(_________________________)

Inference: __________________________________

Prior knowledge

________________________________________

________________

PREDICT AN OUTCOME

If (_________), then (__________).

(must make sense based on your observations)

MUST BE _________________________

1.

If I put on cologne or perfume, then ________

_____________________________________.

2.

If a person______________________________,

Then s/he will lose body fat.

_________________

COLLECT DATA

(See tips below)

Quantitative data: _________________

(Quantity)

Qualitative data: __________________

(Quality)

________________

ANALYZE & CONCLUDE

Summarize data

Return to your hypothesis

Hypothesis ≠ Conclusion: __________________

Hypothesis = Conclusion: __________________

TIPS FOR ENSURING EXPERIMENT IS VALID (acceptable)

Hypothesis: Listening to music on ear phones will cause the highest rate of hearing loss.

1. Sample size = __________________

Ensures not a coincidence

If something goes wrong with a “lab rat,” there

Will be others to collect data from.

2. Number of variables tested at a time: ________

 Too many variables & you won’t know what is

Causing the change.

(similar age ranges, environmental conditions, etc)

3.Control group: ________________________________

4. Tested group: _________________________________

Control Group: ________________________

Tested Group: _________________________

4. Clear procedures

Other scientist can repeat or identify errors if

The steps are clearly communicated.

A hypothesis that “survives” several different experiments with the same result becomes a __

_______________

INDEPENDENT vs. DEPENDENT VARIABLES

An experiment requires a scientist to change or manipulate an object, event, or process to determine how it will affect another object, event, or process. The cause and the effects are often referred to as variables. Like in math, variables can be changed and measured.

INDEPENDENT VARIABLE

(Cause)

DEPENDENT VARIABLE

(Effect)

The variable that is being ___________________________

__________________________by the scientist or naturally.

Examples

1) How does sleep affect a student’s test grade?

IV: ______________________________

Who? __________________

2) How has a population of cardinals grown over the past

100 years?

IV: ______________________________

Who? __________________

The variable that is being ____________________________

Examples:

1) Can Neutrogena face wash decrease acne breakouts?

DV: _____________________________

2) Does height affect how far a person can jump?

DV: _____________________________

3) Do flu infections increase in the fall and winter?

DV: _____________________________

GRAPHING IV & DV:

PRACTICE: Identify the independent and dependent variable in the examples below:

1.

Does participation in extracurricular activities improve academic performance?

IV: _______________________________ DV: _________________________________

Which is the control group? ___________________________________________________________________

2.

Does sex education in schools decrease the spread of sexually transmitted diseases?

IV: _______________________________ DV: __________________________________

Hypothesis: ________________________________________________________________________________

Why? _____________________________________________________________________________________

3.

Do people living in poverty have a higher rate of obesity?

IV: ________________________________ DV: __________________________________

Hypothesis: _______________________________________________________________________________

Why? ____________________________________________________________________________________

Day 2/3 Notes: METHODS of GRAPHING

Graphs help us visualize data so that it is organized in a way that is easy to analyze and make conclusions. There is no right or wrong way to graph data, but in most cases there is a format that will best communicate your data.

__________GRAPH

Function: _____________________________

__________GRAPH

Function: ______________________________

_____________GRAPH

Function: ______________________________

________________PLOT

Function: ________________________________

Up-slope= positive correlation

Down-slope= negative correlation

Flat slope= no correlation

1.

Why is a bar graph the best choice for this data set?

____________________________________________

2.

What is the DV: ______________________________

3.

What is the IV: _______________________________

4.

What age range is the highest rate of infection for both males & females? ____________

5.

What can you infer is the reason why this is the age range for the highest rate of infection?

_____________________________________________

Background information: HIV is a virus that causes AIDS. It is transmitted from person-person through unprotected sex with an infected person, dirty needles used for drugs, and mother to child during pregnancy, birth, or breast milk.

_____________________________________________

6.

What is a possible independent variable that could be tested to determine its effectiveness at decreasing infection rates?

_____________________________________________

_____________________________________________

Day 1a Activity: THE SCIENTIFIC METHOD

Put a check by the question(s) that would be considered scientific.

What clothing fabric absorbs the most sweat?

Which shoe is the best?

What chocolate melts faster, dark or milk chocolate?

Based on the data below, what was the scientific question?

Scientists recently compared the number of calories a woman consumes when she eats with a man versus when

she eats with a women. The study showed that women eat 200 fewer calories when eating with men

compared to eating with women. Over 1,000 women were involved in the study.

Question: _________________________________________________________________________

_________________________________________________________________________

Do you (personally) eat less when you are around the opposite sex? _______________ Why? ______________

____________________________________________________________________________________________

How does your situation compare to the study? _______________________________________________________

Read the experiment below and answer the questions that follow.

Kyla wants to bake a cake for her brother’s birthday. She wants to know which type of milk will make the cake rise best. She conducts an experiment in which she first bakes a cake following the original recipe, using 2 % milk. She then experiments by making 3 more cakes, testing 3 other types of milk (skim, full-fat, and buttermilk).

1.

What is Kyla’s question? ____________________________

_________________________________________________

_________________________________________________

2.

Which cake is the control? ___________________________

2% Skim Full Butter Milk

3.

Based on the data, which milk is the best to use? ___________________

4.

What are 2 other variables that might affect how much the cake rises? __________________________________

5. What should Kayla’s next step be to make her data more valid (acceptable)?

___________________________

Based on the data below, what was the scientific question?

5

Average

Snow fall

Question: ___________________________________

_________________________________________

_________________________________________

Jan Feb. Mar Apr May June July Aug.

The diagram below shows an experimental set-up used to determine which variable will cause plants to grow the tallest in 1 month. Based on the “Tips for Ensuring an Experiment is Valid” section of your notes, what is one suggestion you would make to the scientist to improve the experiment set-up?

Water & yard soil Gatorade & Fertilize

Suggestion: _____________________________________

Why? __________________________________________

__________________________________________

Day 1b Activity: Spongebob Scientific Method - Controls and Variables

SpongeBob and his Bikini Bottom pals have been busy doing a little research. Read the description for each experiment and answer the questions.

Krusty Krabs Breath Mints

Mr. Krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath to try his new

breath mint. He had fifty customers (Group A) eat a breath mint after they finished eating a crabby patty.

The other fifty (Group B) also received a breath mint after they finished the sandwich, however, it was just a regular breath mint and did not have the secret ingredient. Both groups were told that they were getting the breath mint that would cure their bad breath. Two hours after eating the crabby patties, thirty customers in Group A and ten customers in Group B reported having better breath than they normally had after eating crabby patties.

1. Which people are in the control group?

2. What is the independent variable?

S

3. What is the dependent variable?

4. What should Mr. Krabs’ conclusion be?

5. Why do you think 10 people in group B reported fresher breath?

SpongeBob Clean Pants

SpongeBob noticed that his favorite pants were not as clean as they used to be. His friend Sandy told him that he should try using Clean-O detergent, a new laundry soap she found at Sail-Mart. SpongeBob made sure to wash one pair of pants in plain water and another pair in water with the Clean-O detergent. After washing both pairs of pants a total of three times, the pants washed in the Clean-O detergent did not appear to be any cleaner than the pants washed in plain water.

6. What was the problem SpongeBob wanted to investigate?

7. What is the independent variable?

8. What is the dependent variable?

9. What should Sponge Bob’s conclusion be?

T. Trimpe 2003

Squidward’s Symphony

Squidward loves playing his clarinet and believes it attracts more jellyfish than any other instrument he has played. In order to test his hypothesis, Squidward played a song on his clarinet for a total of 5 minutes and counted the number of jellyfish he saw in his front yard. He played the song a total of 3 times on his clarinet and repeated the experiment using a flute and a guitar. He also recorded the number of jellyfish he observed when he was not playing an instrument. The results are shown in the chart.

10. What is the independent variable?

11. What is the dependent variable?

12. What should Squidward’s conclusion be?

13. Are the results reliable? Why or why not?

Super Bubbles

Patrick and SpongeBob love to blow bubbles! Patrick found some Super

Bubble Soap at Sail-Mart. The ads claim that Super Bubble Soap will produce bubbles that are twice as big as bubbles made with regular bubble soap. Patrick and SpongeBob made up two samples of bubble solution.

One sample was made with 5 oz. of Super Bubble Soap and 5 oz. of water, while the other was made with the same amount of water and 5 oz. of regular bubble soap. Patrick and SpongeBob used their favorite bubble wands to blow 10 different bubbles and did their best to measure the diameter of each one. The results are shown in the chart

14. What did the Super Bubble ads claim?

15. What is the independent variable?

16. What is the dependent variable?

17. Look at the results in the chart. a. Calculate the average diameter for each bubble solution.

Super Bubble = ______ cm Regular Soap = ________ cm b. What should their conclusion be?

18. Are the results reliable? Why or why not?

T. Trimpe 2003

STUDY GUIDE

Essential Vocabulary

1. Independent variable:_____________________________________________________________________________

2. Dependent variable:______________________________________________________________________________

3. Control Group:__________________________________________________________________________________

4. Experimental group:______________________________________________________________________________

5. Theory: ________________________________________________________________________________________

6. Hypothesis:_____________________________________________________________________________________

What are 5 things that all scientists should keep in mind when designing an experiment that will produce valid data?

__________________________________________________________________________________________________

Below are two questions that are NOT scientific. Choose one question and REWRITE it in a way that would make it scientific (testable).

Question A: Which AXE body spray is the best?

Question B: Which hair product is the best?

Rewrite:

_________________________________________________________________________

_________________________________________________________________________

EXPERIMENT DESIGN & GRAPHING

Use the data table below to answer all questions

Plant Day 10 Day 12 Day 14 Day 16 Day 18 Day 20

Soil & water

0 0 .75 1.4 2.1 3.2

Soil & Fertilizer A

0.5 3.0 4.5 6.5 9.0 11.0

Miracle Grow

Soil & Fertilizer B

Terra Cycle

(worm poop)

1.0 2.0 3.5 6.0 8.5 12.5

Table 1:

Day 22 Day

24

4.2

13.5

15.0

5.0

15.0

18.0

Total

Growth

5

14.5

17

Daily measurements of tomato plants treated with fertilizers compared to only water.

All measurements shown are heights of plants in centimeters .

1.

Based on the data, what most likely was the scientific question?

__________________________________________

_______________________________________________________________________________________________

3. Which graphing format would be best to communicate the data? _______________

Explain your reasoning: __________________________________________________________________________

4. What is the independent variable? __________________________ Dependent variable: _______________________

5. What is the control group? ________________________________________________

6. Where should the scientist conduct the experiment (in a green house or an open field) __________________________

Explain your reasoning? __________________________________________________________________________

_________________________________________________________________________________________

Graph the data below showing all labels & legends

(Hint: there will be multiple line graphs on the grid below)

Legend ____________ ____________ ___________

Conclusion: ________________________________

__________________________________________

__________________________________________

__________________________________________

__________________________________________

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