1. Applying the Scientific Method
B1.1 Generate hypotheses on the basis of credible, accurate, and relevant sources of scientific information.
B1.4 Design a scientific investigation with appropriate methods of control to test a hypothesis (including independent and dependent variables), and evaluate the designs of sample investigations.
B1.5 Organize and interpret the data from a controlled scientific investigation by using mathematics (including formulas and dimensional analysis), graphs, models, and/or technology.
B1.6 Evaluate the results of a controlled scientific investigation in terms of whether they refute or verify the hypothesis.
B1.7 Evaluate a technological design or product on the basis of designated criteria (including cost, time, and materials).
B1.8 Compare the processes of scientific investigation and technological design.

2. Hypothesis
a reasonable explanation of an observation or experimental result
a possible answer to a scientific question that can be tested.
may or may not be supported by the experimental results.
stated in terms of an independent and a dependent variable—or a “cause-effect relationship.”

3. Examples of hypotheses
*If a leaf has a greater surface area, then the rate at which it produces oxygen may increase.
*If a cell has a higher surface area, diffusion occurs faster.
*At warmer temperatures, mold will grow faster on bread.

4. Practice on your own Write some examples of Hypothesis.
If ____________, then ____________.

5. Format of Scientific Method
this corresponds to the next slides that we can have them fill in as we go along……

6. Question
Stating the purpose in the form of a testable question or problem statement
Researching information related to the investigation

7. Hypothesis testable educated guess
predicts the relationship between an independent and dependent variable
Use credible, accurate and relevant sources

8. Procedure
Plan for independent and dependent variables with repeated trials
Plan for factors that should be held constant (controlled variables)
Plan for a control group to set up as a basis of comparison
Set up the sequence of steps to be followed
List materials

9. Data Recording, organizing and analyzing data: charts graphs
Dependent
Variable
Independent
Variable
Dependent
Independent
Variable

10. Conclusion/Analysis
Conclusion statement that experiment supported or did not support the hypothesis.
Discussion of results to explain why hypothesis supported or not.

11. Conclusion/ Analysis
Results of an experiment cannot prove that a hypothesis is correct. Rather, the results support or do not support the hypothesis
If the data is consistent with the prediction in the hypothesis, the hypothesis is supported.
If the data is not consistent with the prediction in the hypothesis, the hypothesis is refuted.

12. Do You Remember DRY- MIX?
D = Dependent Variable
R = Responds to
Y = Y-axis
M = Manipulated
I = Independent Variable
X = X-axis

13. Variables in Science Experiments
What makes an experiment “fair”?

14. Variables A variable is something that is changed
A constant, or control, is something that does not change

15. Science Experiments Use…
Independent Variable: the one factor that is changed by the person doing the experiment
Dependent Variable: the factor which is measured in the experiment
Constants: all the factors that stay the same in an experiment
(copy these terms to Procedure box)

16. A birdie example…
Imagine you want to see what color of bird feeders your local birds preferred.
If a student wanted to determine whether feeder color has an effect, he might suggest, “if I put up a red, blue, and green feeder, birds will visit the green feeder more” as a hypothesis. He might speculate that the green feeder, being the most “camouflaged” or “natural” might be visited the most.
Red? Blue? Green?

17. Our Constants and Variables
Independent Variable: color of the feeders
Dependent Variable: amount of seed eaten
Constants: everything else that is kept the same, for example:
the location of the feeders
the kind of feeder used
putting the feeders out at the same time
Independent Variable: the one factor that is changed by the person doing the experiment
Dependent Variable: the factor which is measured in the experiment
Constants: all the factors that stay the same in an experiment

18. Our Experimental Design
Constants
Location of feeders
Kind of seed
Type of feeder
Independent
Variable
Red
Blue
Green
Dependent
Amount of Seed Eaten

19. The experiment is FAIR. (ONLY the independent variable can change!)
If everything except the independent variable is held constant, we can say:
The experiment is FAIR.
(ONLY the independent variable can change!)

20. Why is it important to only change the independent variable?
Collect answers…

21. If you don’t…
If you measure a change in the dependent variable, you won’t know whether it is the independent variable that is causing the change.
Give an example: a girl wanted to know whether her dog being out in the backyard scared birds away. She thought it would, because the dog likes to bark a lot and has been known to chase little animals.
For 5 days when the dog was out, she counted for an hour.
For 5 days the dog wasn’t out, she counted for an hour.
After she collected the data, she noticed that birds are actually out MORE when the dog is in the yard. Does that surprise you?
But, what the girl didn’t think of was other things that might effect the number of birds that were out. She began thinking that maybe something else might be going on. She realized that the dog was out on sunny warm days, and not on rainy, cool days.
So, even though she found a change, how will she know if it was the dog may have had an effect? Or was it the weather?
See if kids can suggest improvements to the experiment. (i.e. making sure the weather and temperature is similar on the days she counts.)

22. Scenario #1
Sam wants to know if birds prefer one color of feeder to another. He makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. He fills the feeders with the same amount of sunflower seed, and plans to keep the feeders out for one week before measuring how much seed is eaten out of each. On Tuesday, he puts each of the feeders in his back yard: the red feeder in a large dead tree, the blue feeder he sits on the doghouse, and the green one he puts in a small bushy tree.

23. Is Sam’s experiment fair? YES? NO?
Read the following scenario to the students:
Sam wants to know if birds prefer one color of feeder to another. He makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. He fills the feeders with the same amount of sunflower seed, and plans to keep the feeders out for one week before measuring how much seed is eaten out of each. On Tuesday, he puts each of the feeders in his back yard: the red feeder in a large dead tree, the blue feeder he sits on the doghouse, and the green one he puts in a small bushy tree.
Is Sam’s experiment fair?
NO! It isn’t fair since the locations of the feeders were very different!

24. Scenario #2
Maria wants to know if birds prefer one color of feeder to another. She makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. She fills each of the feeders with the same amount of mixed birdseed, and plans to keep the feeders out for 10 days before measuring how much seed is eaten from each feeder. She puts each of the feeders in the school courtyard in a small tree, hanging each at the same height.

25. Is Maria’s experiment fair? YES? NO?
Read the following scenario to the students:
Maria wants to know if birds prefer one color of feeder to another. She makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. She fills each of the feeders with the same amount of mixed birdseed, and plans to keep the feeders out for 10 days before measuring how much seed is eaten from each feeder. She puts each of the feeders in the school courtyard in a small tree, hanging each at the same height.
Does Maria’s experiment seem fair?
YES! It seems fair since Maria only changed the feeder color!

26. Scenario #3
Jessie wants to know if birds prefer one color of feeder to another. She makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. She fills the each of the feeders with sunflower seed. She plans to leave each feeder out for 2 days and then measure the amount of seed that the birds ate. She has one hook in her backyard the she plans to hang each of the feeders on. She puts the red feeder out on Tuesday and measures the seed 2 days later, the green feeder doesn’t go out until Saturday since it was very snowy, but she is able to measure the seed 2 days later. The weather turned rainy, but she needs to finish her experiment, so blue feeder goes out on Monday and is measured 2 days later.

27. Is Jessie’s experiment fair? YES? NO?
NO! It isn’t fair since the feeders are not out at the same time, and we know that the weather was quite different each time. Perhaps the number and kind of birds that visited during the weeks were different due to the weather.
Read the following scenario to the students:
Jessie wants to know if birds prefer one color of feeder to another. She makes three feeders out of 2-liter bottles and paints one red, one blue, and one green. She fills the each of the feeders with sunflower seed. She plans to leave each feeder out for 2 days and then measure the amount of seed that the birds ate. She has one hook in her backyard the she plans to hang each of the feeders on. She puts the red feeder out on Tuesday and measures the seed 2 days later, the green feeder doesn’t go out until Saturday since it was very snowy, but she is able to measure the seed 2 days later. The weather turned rainy, but she needs to finish her experiment, so blue feeder goes out on Monday and is measured 2 days later.
Is Jessie’s experiment fair?

28. What do you think?
Terry loves birds and wants to see as many as she can in her yard. She wants to know whether she is wasting money buying an expensive mixed seed, when a cheaper brand just arrived at her local store. She wonders… will the expensive seed attract more birds to her back yard?
You may want to have students brainstorm in pairs, or conduct a group discussion.
How would you advise her to find out if the expensive seed is better?

29. Terry’s Experimental Design
Independent
Variable ?
Dependent
Constants
What is the Independent Variable?
What is the Dependent Variable?
What would you hold constant?

30. Terry’s Experimental Design
Independent
Variable
Kind of seed:
Expensive Cheap
Dependent
Number (and perhaps kinds) of birds that visit
Constants
Location of feeders
Type of feeder
Way she measures the amount of seed eaten and the way she counts birds
What is the Independent Variable?
What is the Dependent Variable? Number of birds– also, you may want to record what KINDS visit. Maybe diversity is higher with one seed or the other!
What would you hold constant? There are other answers as well. Feel free to add to the list

31. What experiments are you planning?
What are your variables?
How will you keep your experiment fair?

32. Activity 2 – Identify the Controls and Variables
Scenario #1
Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.
Identify the:
Control Group
2. Independent Variable
3. Dependent Variable
4. What should Smithers' conclusion be?
 5. How could this experiment be improved?
6. What was the initial observation?

33. Activity 2 – Identify the Controls and Variables
Scenario #2
Homer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of "treatment" there is no change in the appearance of the green slime on either side of the shower.
Identify the:
7. Control Group
8. Independent Variable
9. Dependent Variable
10. What should Homer's conclusion be?

34. Activity 2 – Identify the Controls and Variables
Scenario #3
Bart believes that mice exposed to radiowaves will become extra strong (maybe he's been reading too much Radioactive Man). He decides to perform this experiment by placing 10 mice near a radio for 5 hours. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. he found that 8 out of 10 of the radiowaved mice were able to push the block away. 7 out of 10 of the other mice were able to do the same.
Identify the:
11. Control Group
12. Independent Variable
13. Dependent Variable
14. What should Bart's
conclusion be?
15. How could Bart's experiment be improved?

35. Activity 2 – Identify the Controls and Variables
Scenario #4
Krusty was told that a certain itching powder was the newest best thing on the market, it even claims to cause 50% longer lasting itches. Interested in this product, he buys the itching powder and compares it to his usual product. One test subject (A) is sprinkled with the original itching powder, and another test subject (B) was sprinkled with the Experimental itching powder. Subject A reported having itches for 30 minutes. Subject B reported to have itches for 45 minutes.
Identify the:
16. Control Group
17. Independent Variable
18. Dependent Variable
19. Explain whether the data supports the advertisements claims about its product.

36. Activity 2 – Identify the Controls and Variables
Scenario #5
Lisa is working on a science project. Her task is to answer the question: "Does Rogooti (which is a commercial hair product) affect the speed of hair growth". Her family is willing to volunteer for the experiment.
Identify the:
20. Describe how Lisa would perform this experiment. Identify the control group, and the independent and dependent variables in your description.

37. The shape of a graph can show the relationship between the variables in the hypothesis.

38. The shape of a graph can show the relationship between the variables in the hypothesis.

39. Activity 3 – Pulling it all together…
Homework: Lessons 1 – 6 walks through scientific method

40. Activity 4
Gummy bear lab

41. Scientific Models
are descriptions of how phenomena occur and how data or events are related.
are used to represent a concept or system so that the concept may be more easily understood and predictions can be made.
Models may change over time as scientific knowledge advances.

42. Technology
tools/machines or processes that can be used to develop better understanding of the science concepts studied.
We can organize and analyze data using technology such as graphing calculators or computers.

43. Technological designs
Are produced by the application of scientific knowledge to meet specific needs of humans.
There are four stages of technological design:
Problem identification
Solution design (a process or a product)
Implementation
Evaluation

44. Technological designs
Common requirements within the solution design stage of all technological designs or products include:
Cost effectiveness or lowest cost for production;
Time effectiveness or the least amount of time required for production, and
Materials that meet specific criteria, such as:
Solves the problem
Reasonably priced
Availability
Durability
Not harmful to users or to the environment
Qualities matching requirements for product or solution
Manufacturing process matches characteristics of the material
Understand that benefits need to exceed the risk.
There are tradeoffs among the various criteria. For example, the best material for a specific purpose may be too expensive.

45. Notes
1. Science is a process of inquiry that searches for relationships that explain and predict the physical, living and designed world.
2. Technology is the application of scientific discoveries to meet human needs and goals through the development of products and processes.

46. Notes (cont)
3. The processes of scientific investigation are followed to determine the relationship between an independent and dependent variable described by a hypothesis.
4. The processes of technological design are followed to design products or processes to meet specified needs. The results of technological designs can advance standard of living in societies.
5. In general, the field of engineering is responsible for technological designs or products by applying science to make products or design processes that meet specific needs of mankind.