# Not just for scientists!

## Presentation on theme: "Not just for scientists!"— Presentation transcript:

Not just for scientists!
The Scientific Method Not just for scientists! Adapted from

What is it? The scientific method is a logical sequence of steps that people use to identify, test, and answer a problem. It is broken down into six steps: State the problem. Form a testable hypothesis. Design an experiment. Collect and analyze data. Draw conclusions. Communicate results. Have students fill in notes in each appropriate box on the SM Cheat Sheet

Taking a closer look… Choosing a question or problem to solve:

Examples of good questions…
How does the size of a wheel affect the speed of a Hotwheel’s car? How does color affect people’s food choices? How does age affect a person’s reaction time? How does the amount of water affect the growth of a plant?

Checkpoint! How are rainbows formed? Good question. Unsafe question.
Difficult to get materials. No manipulated and responding variables. Correct answer is D. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

How does eating food affect a person’s growth?
Good question. Answer is already known. Difficult to get materials. Unsafe question. Correct answer is B. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

In a crash, how does the speed of the train affect the amount of damage to a non-moving car?
Good question. Question is not interesting. Difficult to get materials. No manipulated and responding variables. Correct answer is C. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

How does the type of liquid affect plant growth?
Good question. Unsafe question. Difficult to get materials. No manipulated and responding variables. Correct answer is A. This is a good question to investigate because it is safe, interesting, contains a manipulated and responding variable, is inexpensive, and is probably something you would not find in an encyclopedia.

Taking a closer look… Creating a testable hypothesis:
“I predict that…” Include a statement that shows cause and effect. It must address the manipulated and responding variables. Right or wrong does not matter! Tip 2 - An "If...then..." statement is one that shows a cause and an effect relationship. For example, "If a plant is given acidic liquids, then the plant's growth will decrease." In this hypothesis, there is a cause (acidic liquid) that produces an effect (decrease in plant growth). Tip 3 - The cause and effect in your hypothesis are related to the manipulated and responding variables in your question. For example, look at this question: "How does the type of music affect a plant's growth?" The type of music can be changed intentionally, so it is the manipulated variable. The plant's growth may change as a result of the type of music, so it is the responding variable. Your hypothesis must include an MV and RV: "I think that if a plant is exposed to classical music (MV), then it will grow very fast (RV)." Tip 4 - At the end of the experiment you will find out whether your hypothesis was right or not. As a scientist, you should understand that it is not important that you "got it right." It is more important that you learned something about your topic. Don't get hung up on having the right answer.

Examples of good hypotheses…
I predict that if a student reviews their science notes 30 minutes each day, their science test scores will improve. I predict that the longer the mealworm the faster it will travel in a given length. I predict that if a plant receives too much water it will become unhealthy and die.

Checkpoint! Q - How does color affect a person’s food choices?
H – I predict that if a person sees a red sweater, they will choose it over one of a different color. “I predict that…” is missing. There is no cause and effect statement. Does not answer the question. Good hypothesis. Correct answer is C. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

Q - How are paper towel brand names and absorbencies related?
H – If the brand name is expensive then its absorbency will be higher. “I predict that…” is missing. There is no cause and effect statement. Does not answer the question. Good hypothesis. Correct answer is A. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

Q - How does age affect a person’s reaction time?
H – I predict that if a person is older, they can react. “I predict that…” is missing. It does not include a MV and RV. Does not answer the question. Good hypothesis. Correct answer is B. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

Q - How does the size of a wheel affect the speed of a Hotwheel car?
H – I predict that a car with larger wheels will go slower than a car with smaller wheels. “I predict that…” is missing. There is no cause and effect statement. Does not answer the question. Good hypothesis. Correct answer is D. Read the question. Decide whether the question is a good one for a middle school student to investigate or not. Raise the letter of the answer you believe is correct.

Good morning… Pass back graded work (2 volunteers please)
Review Vocabulary Terms and SM Cheat Sheet Steps 1 and 2 quietly Step #3 of Scientific Method: Design an Experiment (need Cheat sheet) Why common measuring system? Metrics experts

Metrics Experts Working in rows: read your purple book pages to learn about your assigned topic Work together to create 1 page describing the topic Be prepared to teach your topic to the class using the document camera

Taking a closer look… Designing an experiment:

Example of designing an experiment:
Question – How does the amount of water affect plant growth? Hypothesis – I predict that if a plant receives too much water it will become unhealthy and die. Experiment Design: Constants: type & age of plant, type & size of pot, amount & types of soil, amount of sunlight, type & time of water provided, time of day growth is measured. Manipulated Variable: ? Materials needed: 5 identical pots, soil, 5 identical bean seeds, water, graduated cylinder, sunny window. Measuring data: Soil will be measured in grams, water will be measure in milliliters, growth will be measured in centimeters, growth will be measured from the soil to the tallest part of the plant.

Example of procedures:
Measure 300 g of soil and pour into plastic pot. Repeat for each pot. Place 3 bean seeds on the top of the soil in each pot. Measure 100 g more of soil and sprinkle over beans. Repeat for each pot. Place all 5 pots in a sunny window. All pots should be positioned to receive the same amount of light. Label each pot with a number using a sharpie. Pots will be numbered Measure 10 ml of water and pour into pot #1. Measure 20 ml of water and pour into pot #2. Put 30 ml in pot #3, 40 ml in pot #4, and 50 ml in pot #5. Record date in log book along with water measurements for each pot. Check plants at 4pm every day. Measure and record height (in cm) for each plant daily. Which of these procedure #’s contains the mv?

Checkpoint! Question: How does color influence people's food choices?

Question: How does color influence people's food choices?
Hypothesis: I predict that if people see a red cookie, then they will choose it over any other color of cookie offered to them. Materials: sugar, flour, milk, butter, food coloring (blue, red, yellow, and green), oven, cookie sheet, cookie cutter, bowls, spoons, spatula, measuring cups, serving tray, 10 girls who are years old. Correct. Some materials listed are not necessary. Some materials are missing. Material list does not fit the problem or hypothesis. Correct answer is A.

Question: How does color influence people's food choices?

Taking a closer look… Collect and analyze data:

Data Table Example – The effects of water on plant growth.
Manipulated Responding Variable Variable Amount of Water (ml) Height of Plant (cm) A data table is the easiest way you can record your information. It looks like the diagram below. The manipulated variable is always placed on the left side of the table, and the responding variable is always located on the right side. When you get your data, simply put it into the table. When you record data in a table, be sure to list the manipulated variable numbers in the left column from smallest to largest. Also, the numbers for the manipulated variable should fall into a pattern (for example, by ones - 1, 2, 3, 4, 5; by fives - 5, 10, 15, 20, 25; by hundreds - 100, 200, 300, 400, 500).

Checkpoint! Chart Correct.
Manipulated variable does not have a pattern of numbers. The MV are out of order. The MV and RV are on the wrong sides. Correct answer is D. On the following pages are some data tables. Look at each table carefully and decide whether it contains correct information.

Chart Correct. Manipulated variable does not have a pattern of numbers. The MV are out of order. The MV and RV are on the wrong sides. Correct answer is C. On the following pages are some data tables. Look at each table carefully and decide whether it contains correct information.

Chart Correct. Manipulated variable does not have a pattern of numbers. The MV are out of order. The MV and RV are on the wrong sides. Correct answer is A. On the following pages are some data tables. Look at each table carefully and decide whether it contains correct information.

Chart Correct. Manipulated variable does not have a pattern of numbers. The MV are out of order. The MV and RV are on the wrong sides. Correct answer is B. On the following pages are some data tables. Look at each table carefully and decide whether it contains correct information.

Taking a closer look… Collect and analyze data(Graph):
MV on the x axis and the RV on the y axis. Use a pattern of numbers for each axis.* Include units (m, l, g) and a title. Plot your data. Tip 1 - Take the raw data from your data table and use the exact same numbers in your graph. Remember that you must keep the number from the manipulated variable side with its counterpart on the responding variable side. These two matching numbers are called ordered pairs, and they cannot be separated from one another. They always go together. Tip 2 - The horizontal axis (or x axis) on a graph shows the manipulated variable. Therefore, you must write your MV just below the x axis on your graph. The vertical axis (or y axis) represents the responding variable in your experiment. Write your RV to the left of the y axis on the graph. Tip 3 - Once you label the manipulated and responding variables on your graph, you must also include how you will operationally define each of these variables. For example, if you are measuring length, you might operationally define the variable with millimeters, meters, or kilometers. Be sure to use abbreviations when operationally defining variables, and only use Metric measurements. Tip 4 - This pattern must cover the smallest and largest numbers in your manipulated and responding variables. A pattern is a series of numbers that adds an equal amount for each successive number. Look at the examples of number patterns below.

Pattern of numbers Look at the data table below.
What would be a good pattern for the MV numbers? How about the RV numbers? A good pattern for the manipulated variable would be (2, 4, 6, 8, 10). The numbers are already arranged by twos, so this part is easy. A good pattern for the responding variable might be (12, 14, 16, 18, 20). This pattern covers the smallest number on the RV side (14) and the largest number (18).

Plot the Data To plot data, start with the x axis and find your first number under the MV column on your data table. In the table below, the first number is 2. Then, on the y axis, find the corresponding number from the RV column on your data table. In the table below, the corresponding number is 14. Draw one imaginary line up from the x axis and another imaginary line to the right on the y axis until the two lines intersect. The point of intersection is where you should plot your point. Repeat this process for all of your ordered pairs on the data table.

Finished Example The title of your graph must relate directly to your manipulated and responding variables. It is a good idea to include both the MV and RV in the title.

Checkpoint! Graph Correct. MV and RV are labeled on the wrong axis.
Number pattern is incorrect. Data not plotted correctly. Correct answer is C. The number pattern for the responding variable is incorrect. It should be written using a pattern of ones (1, 2, 3, 4, 5).

Graph Correct. MV and RV are labeled on the wrong axis.
Number pattern is incorrect. There is no title included. Correct answer is D.

Graph No units of measurement for MV & RV.
MV and RV are labeled on the wrong axis. Number pattern is incorrect. There is no title included. Correct answer is B. The manipulated variable should be written on the x axis, and the responding variable should be written on the y axis.

Graph No units of measurement for MV & RV.
MV and RV are labeled on the wrong axis. Number pattern is incorrect. There is no title included. Correct answer is A.

Graph Data plotted incorrectly. Correct. Number pattern is incorrect.
No units of measurement for MV & RV. Correct answer is A. The last ordered pair has been plotted incorrectly.

Taking a closer look… Drawing conclusions:
Restate your problem and hypothesis. Summarize your procedures. Explain how the MV affected the RV. (What does the graph show?) Explain whether or not the results supported your hypothesis. If not, why? Future experiments.