Experimental Design Diagram Goal: Construct an Experimental Design Template on your proposed research project

Steps to Constructing an Experimental Design Diagram Step 1: Write a title: The Effect of the Independent Variable (IV) on the Dependent Variable (DV). Example: The Effect of Various Amounts of Calcium Chloride on the Temperature of Water

Steps to Constructing an Experimental Design Diagram Step 2: State a hypothesis If the (independent variable) is (describe how you changed it), then the (dependent variable) will (describe the effect). Example: If more scoops of calcium chloride are added to water, them the temperature of the water will increase.

Steps to Constructing an Experimental Design Diagram Step 3: Write your independent variable (IV). Example: Amount of Calcium Chloride Scoops: 1 scoop, 2 scoop, 3 scoop * In Science Research, we will be testing varying concentrations of chemicals/solutions.*

Steps to Constructing an Experimental Design Diagram Step 4: Divide the bottom two rows into columns, one column for each level of the independent variable. Write the levels of the IV in the columns. If one of those levels is the control for the experiment, put the word control under than level. Example: shown in complete table at the end

Steps to Constructing an Experimental Design Diagram Step 5: In each column, write the number of repeated trials conducted for each level of the IV. Your designed experiment should have at least 2-3 repeated trials. Great number of trials will ensure the validity of your results. Example: shown in complete table at the end

Steps to Constructing an Experimental Design Diagram Step 6: Write your Dependent Variable (DV) The dependent variable is the measureable effect. Example: Temperature of the water.

Steps to Constructing an Experimental Design Diagram Step 7: Write a list of the constants (C) The constants are items that remain unchanged throughout the experiment and for each variable being tested. Example: Same amount of water (75 mL), Same time to dissolve (2 minutes), Constant stirring

Experimental Design Diagram Title: Hypothesis: IV: Control: Trials: Variable 1: Variable 2: Trials Variable 3: DV: Constants:

Experimental Design Diagram: Example Title: The Effect of Various Amounts of Calcium Chloride on the Temperature of Water Hypothesis: If more scoops of calcium chloride are added to water, them the temperature of the water will increase. IV: Amount of Calcium Chloride Scoops: Control: 0 scoops Trials: 3 trials Variable 1: 1 scoop Variable 2: 2 scoops Variable 3: 3 scoops DV: Temperature of the water Constants: Same amount of water ( 75 mL), Same time to dissolves (2 minutes), constant stirring

Checking the Design: Does the title identify both the IV and DV? Does the hypothesis clearly state how you think changing the IV will affect the DV? (is it specific?) Is there an IV? Are the levels of the IV clearly stated? Are there enough levels of the IV tested? Is there a control? Is it clearly stated? Are there repeated trials? Are there enough of them? Is the DV clearly identified and stated?

Checking the Design: Is the DV operationally defined? (operationally defined means that the investigator very clearly stated how the response would be measured or described) Are the constants clearly identified and described? Are there any others? Did the experimental design diagram include all the parts listed in the example? Was the experiment creative? Was it an appropriate level of complexity?

Checklist for Evaluating Experimental Design: Criteria/Value (100 points) Self Peer Teacher Title (5) Hypothesis (5) Independent Variable (10) Levels of Independent Variable (10) Control (10) Repeated Trials (10) Dependent Variable (10) Operational definition of dependent variable (10) Constants (15) Experimental design diagram (10) Creativity/complexity (5)

Practice Activity 2.1 “Design Detective” Create an Experimental Design Diagram for Scenario 5 “Aloe Vera and Planaria.”

Review:

Experimental Design Diagram: Scenario 5

HW: Due tomorrow: Answer Questions 1 and 4 (A-D) A – C can be answered in an Experimental Design Diagram. D (improvements of the study) can be mentioned in separate sentences underneath the Experimental Design Diagram.