Improving scientific thinking and experimental design skills in undergraduate students Angela Hodgson, North Dakota State University Fiona Rawle, University.

Improving scientific thinking and experimental design skills in undergraduate students

Angela Hodgson, North Dakota State UniversityFiona Rawle, University of Toronto at Mississauga.

How did this collaboration start? Talked at BLC Emailed each other after BLC Applied for and received catalytic grant

THANK YOU Jane Reece, the family of Neil Campbell, and Pearson for your support!

Rationale – Science Process Skills What are science process skills?

Experimental Design Graphing and visualizing data Statistical analysis and hypothesis testing Scientific communication

Why are science process skills important?

Comparison of Classes

UTM NDSU

Class Intro to Evolution

General Biology I

Size 2 x 380 2 x 350-400

Lab Size

24; weekly 1.5 hr lab

24; weekly 2 hr lab

Semester Length

12 weeks 16 weeks

Learning Outcomes

1. Explain what a hypothesis is.

2. Identify good vs bad hypotheses.

3. Identify elements of good experimental design.

4. Identify independent and dependent variables in an experimental design.

5. Explain the importance of replication in experimental design.

6. Critique an experiment.

7. Improve upon a prior experimental design.

8. Design an experiment to test a hypothesis.

1. Write a good hypothesis

2. Identify independent and dependent variables in an experimental design

3. Design an experiment to test a hypothesis.

4. Record and analyze scientific data in a spreadsheet

5. Perform a statistical hypothesis test

6. Create graph that correctly represents scientific data

7. Interpret and synthesize results from a scientific experiment

UTM intervention NDSU Intervention

UTM – Course Design

Introductory Biology

Course Re-Design

1. “Thinking

Like a Scientist” Introductory Module

2. Case Study Based Tutorial

Sessions3. Inquiry

Based Labs

4. “Science

vs. Pseudosci

ence” Lecture

Examples

5. Scientific Literacy

Assignment

6. Active Learning Exercises in Lecture

1.

12.

Module: Thinking Like a Scientist

Module: Critiquing Scientific Literature

Lecture Intervention

Lab Intervention

Assessment

Module: Experimental

Design

EDATWorksheets on

hypothesis Testing and

experimental design included

in every lab

EDAT, Final Exam

Science Process Skills Concept

Assessment

Group EDAT

Science vs Pseudoscience

Clicker Case Studies

Group Experimental

Design Brainstorming

Session

In class example - UTM

“You should take chlorophyll supplements because your need to oxygenate your bowel”

(See “Bad Science” by Ben Goldacre)

Week #

1.

16.

Lab Intervention Assessment

EDAT pretest

EDAT, SPARST 2nd Lab Practical

1st Lab Practical

Inquiry Lab – Optimization of ethanol production(Yeast respiration)

Inquiry Lab: Optimization of commercial osmotic dehydration

(Diffusion and osmosis)

Inquiry Lab: Optimize greenhouse photosynthetic rate

(Spectrophotometry and Photosynthesis

Inquiry Lab: Does race exist?From Peggy Brickman

(ABLE proceedings Vol. 32)(DNA electrophoresis)

NDSU – Example Inquiry Lab

Question

Agri-gas is a company currently producing ethanol by yeast fermentation of a 5% sucrose solution at 20°C. The company would like to increase the metabolic rate of the yeast in order to maximize ethanol production. Would changing any aspect of the current production system increase the rate of yeast fermentation?Materials

Incubators that can be set at 40 degrees C and 60 degrees C, refrigerator (4 degrees C), carbohydrates- sucrose(table sugar), glucose, brown sugar, powdered sugar, lamps with different color light bulbs, dark cabinets, HCl (acid), base (NaOH)

Experimental Design Aptitude Test(Sirum, 2011 Bioscience)

• Students taking the EDAT are given the following prompt:

• Advertisements for a herbal product, ginseng, claim that it promotes endurance. To determine if the claim is fraudulent and prior to accepting this claim, what type of evidence would you like to see? Provide details of an investigative design.

EDAT Scoring Rubric

1 pt. is awarded for each of the following rubric items that are included in the student answer.

1.Recognition that an experiment can be done to test the claim2.Identification of what variable is manipulated3.Identification of what variable is measured4.Description of how dependent variable is measured5.Realization that there is one other variable that must be held

constant6.Understanding of the placebo effect7.Realization that there are many variables that must be held

constant8.Understanding that the larger the sample size or number of

subjects, the better the data.9.Understanding that the experiment needs to be repeated.10. Awareness that one can never prove a hypothesis, that one

can never be 100% sure.

UTM: Pre and Post EDAT

UTM: Pre and Post Rubric Item Score

NDSU: Pre and Post EDAT

N=517

NDSU: Pre and Post Rubric Item Score

N=517

Learning Outcomes

1. Write a good hypothesis

2. Identify independent and dependent variables in an experimental design

3. Design an experiment to test a hypothesis.

4. Record and analyze scientific data in a spreadsheet

5. Perform a statistical hypothesis test

6. Create graph that correctly represents scientific data

7. Interpret and synthesize results from a scientific experiment

NDSU: Additional Rubric Items11. Identified that a hypothesis is needed/wrote a hypothesis. 12. Identified that a null hypothesis is needed for hypothesis testing, or wrote a null hypothesis. 13. Stated that treatment means need to be significantly different to reject the null hypothesis.

NDSU: Additional Pre and Post Rubric Item Scores

What we learned?

Future Directions

Combine the NDSU (inquiry labs) and UTM (lecture modules) interventions

Use an expanded rubric for assessment.

Use the Science Process and Reasoning Skills Test (SPARST) developed by Clarissa Dirks and Mary Pat Wenderoth.

Acknowledgements

This project was funded by a Catalytic Grant. We thank Jane Reece, the family of Neil Campbell, and Pearson for this opportunity.

Clarissa Dirks and Mary Pat Wenderoth gave us access to SPARST, which we also used as a post-test.

We also thank our students that took part in this study, and our teaching assistants.

Science Process and Reasoning Skills Test

Learning Outcome Identify a hypothesis Identify a controlling variable Evaluate the quality of the experiment to test the hypothesis Choose a supporting hypothesis Analyze treatments and controlling for variables Apply knowledge of appropriate controls Select prediction Evaluate experimental design to determine if the conclusion is

warranted Evaluate experimental designs to determine which will yield valid

results Compare and identify the variables for which one should control Compare and identify the variables for which one should control