Research on Alternative Conceptions in Students: the Carbon Cycle Diane Ebert-May

Department of Plant Biology Michigan State University www.first2.org

Collaborators

        Doug Luckie - Physiology Janet Batzli - Plant Biology (University of Wisconsin) Scott Harrison - Microbiology Tammy Long - Plant Biology Jim Smith - Zoology Deb Linton - Plant Biology Heejun Lim - Chemistry Education Duncan Sibley - Geology

Question 1

Please respond on a scale of 0 - 100 in increments of 10: How important is it to use data to assess student learning?

How important is it to use data to assess student learning? 40 35 30 25 20 15 10 5 0 10 20 30 not important 40 50 60 70 80 90 important 100

Question 2

Please respond on a scale of 0 - 100 in increments of 10: How often do I use data to make instructional decisions?

How often do you use data to make instructional decisions?

15 10 5 0 30 25 20 0 10 not often 20 30 40 50 60 70 80 90 often 100

True or False?

 Assessing student learning in science actually parallels what scientists do as researchers.

Assessment in Teaching Parallels Assessment in Research        We ask questions and develop hypotheses to solve problems about learning.

Questions are based on current knowledge and theories and creative, original and interesting to the investigator.

Research designs and methods used to collect data are logical arguments to answer questions.

Instruments/techniques we use are valid, repeatable measures of learning.

Assessment (results) help us understand student thinking.

Results drive our next questions or decisions about a course.

Our ideas are peer reviewed - informally or formally

What is assessment?

Data collection with the purpose of answering questions about… » students’ understanding » students’ attitudes » students’ skills » instructional design and implementation

Graduate Education

 Often excellent at preparing individuals to design and carry out disciplinary research.

Graduate Education

  Often inadequate and haphazard in preparing future faculty/professionals to take on the increasingly complex demands of the professoriate.

Teaching not - mentored, peer reviewed, or based on accumulated knowledge

Solution: a model

 Intergenerational teams in cooperative academic environments » Who: senior faculty, junior faculty, postdoctoral and graduate students. » What: Scholarship of science teaching and learning is fully integrated into the professional culture along with discipline-based activities.

Recognizing and Rewarding

Evaluating and Improving Undergraduate Teaching in Science, Technology, Engineering, and Mathematics (2003)

» National Research Council » www.nap.edu/catalog/10024.html

What are central questions about learning?

1. What do we want our students to know and be able to do?

2. What knowledge or misconceptions do our students bring to the course?

3. What evidence will we accept that students know and can do?

4. How does our teaching help learning?

What Type of Learning?



Bloom (1956) Major categories in the Cognitive Domain of Educational Objectives

Convergent Thinking

   Knowledge - remember material Comprehension - grasp the

meaning of material

Application - use learned material

in new concrete situations

– Adapted from Grolund (1970)

Divergent Thinking

   Analysis - break down material to

understand organizational structure

Synthesis - put parts together to form

a new whole

Evaluation - judge value of material for

a purpose

– Adapted from Grolund (1970)

Research Question How can diagnostic assessment questions help us understand students’ thinking about the carbon cycle?

Background

  Conceptual change theory Force Concept Inventory (David Hestenes -> Physics Dept., ASU)

Carbon Cycle = Rich Problem

    Why?

Integrates many biological concepts at multiple scales.

Instruction can return to elements intrinsic in the carbon cycle - bioenergetics, metabolism. Several documented student misconceptions associated with the carbon cycle.

Real-world applied consequences if students continue to misunderstand.

Some Common Misconceptions about Photosynthesis & Respiration Concept 1: Matter disappears during decomposition of organisms in the soil.

Concept 2: Photosynthesis as Energy: Photosynthesis provides energy for uptake of nutrients through roots which builds biomass. No biomass built through photosynthesis alone.

Concept 3: Thin Air: CO 2 and O 2 are gases therefore, do not have mass and therefore, can not add or take away mass from an organism.

Concept 4: Plant Altruism: CO 2 organisms can ‘breathe’.

is converted to O 2 in plant leaves so that all Concept 5: All Green: Plants have chloroplasts instead of mitochondria so they can not respire.

Instructional Design

 Active, inquiry-based learning » Cooperative learning » » Questions, group processing, large lecture sections, small discussion sections, multi-week laboratory investigations Homework problems including web-based modules

Students - Introductory Biology

(majors)

Two courses:

» Bio 1 - organismal/population biolgy (semester) » Bio 2 - cell and molecular biolgy (semester)

Three cohorts:

» Cohort 1 Bio 1 » » Cohort 2 Bio1/Bio2 Cohort 3 XXX/Bio2

Assessment Design

   Multiple iterations/versions of the carbon cycle problem Pretest, midterm, final with additional formative assessments during class Administered during instruction » Semester 1 - pretest, midterm, final exam » Semester 2 - final exam

Multiple choice question

(pre-post) The majority of actual weight (dry biomass) gained by plants as they progress from seed to adult plant comes from which one of the following substances?

a. Particle substances in soil that are take up by plant roots. (15%).

b. Molecules in the air that enter through holes in the plant leaves (4%).

c. Substances dissolved in water taken up directly by plant roots. (28%).

d. Energy from the sun (29%).

N=138

Radish Problem (formative)

   Experimental Setup: Weighed out 3 batches of radish seeds each weighing 1.5 g.

Experimental treatments: » 1. Seeds placed on moistened paper towels in LIGHT » » 2. Seeds placed on moistened paper towels in DARK 3. Seeds not moistened (left DRY) placed in light

Radish problem

(2)   After 1 week, all plant material was dried in an oven overnight (no water left) and plant biomass was measured in grams. Predict the biomass of the plant material in the various treatments. » Water, light » » Water, dark No water, light

Results: Weight of Radish Seeds

1.46 g 1.63 g 1.20 g Write an explanation about the results.

Evaluation

    Reports from groups Peer evaluation Individual evaluation by instructor Maximum score - 5 points

Whale Problem

(midterm F01) Two fundamental concepts in ecology are “energy flows” and “matter cycles”. In an Antarctic ecosystem with the food web given above, how could a carbon atom in the blubber of the Minke whale become part of a crabeater seal? Note: crabeater seals do not eat Minke whales. In your response include a drawing with arrows showing the movement of the C atom.

In addition to your drawing, provide a written description of the steps the carbon atom must take through each component of the ecosystem Describe which biological processes are involved in the carbon cycle.

Grandma Johnson Problem

(final Fall 01) Hypothetical scenario: Grandma Johnson had very sentimental feelings toward Johnson Canyon, Utah, where she and her late husband had honeymooned long ago. Her feelings toward this spot were such that upon her death she requested to be buried under a creosote bush overlooking the canyon. Trace the path of a carbon atom from Grandma Johnson’s remains to where it could become part of a coyote. NOTE: the coyote will not dig up Grandma Johnson and consume any of her remains.

Jaguar Problem

(final, Spr 02) Deep within a remote forest of Guatemala, the remains of a spider monkey have been buried under an enormous mahogany tree. Although rare, jaguars have been spotted in this forest by local farmers. Use coherently written sentences and clearly labeled drawings to explain how a carbon atom in glucose contained within muscle cells of the spider monkey might become part of a cell within the stomach lining of a jaguar. (Note:The jaguar does not dig up the monkey and eat the remains!) Include in your answer descriptions of the key features (not complete biochemical pathways!) of the organismal and cellular processes that explain how the carbon atom of the monkey’s corpse could become a part of the jaguar’s body.

Analysis of Responses

Used same scoring rubric for all three problems - calibrated by adding additional criteria when necessary, rescoring: Examined two major concepts: Concept 1: Decomposers respire CO 2 Concept 2: Plants uptake of CO 2 Explanations categorized into two groups: Organisms (trophic levels) Processes (metabolic)

100 80 % 60 40 20 0 Trace Carbon from Whale to Seal (Bio1 students, n=141)

Organism Process

Concept 1 Decomposers respire CO 2 Concept 2 Plants uptake CO 2

100 80 % 60 40 20 0 Cellular Respiration by Decomposers (Bio1/Bio2 students, n=63) Q 1 Whale Q 2 Grandma J Concept 1: Decomposers respire CO 2 Q 3 Jaguar  2 (2) = 20.16, p < 0.01

100 80 % 60 40 20 0 Pathway of Carbon into Primary Producer (Bio1/Bio2 students, n=63) Q 1 Whale Q 2 Grandma J Q 3 Jaguar Concept 2: Plants uptake CO 2  2 (2) = 4.778, p = .092

Air Root

Trace Carbon from Spider Monkey to Jaguar (Bio2) 100 80 % 60 40 20 0 Respiration NA Bio1 + Bio2 (n=63) 0ther + Bio2 (n=40) Concept 1: Decomposers respire CO 2  2 (1) = 14.59, p < .01

100 80 % 60 40 20 0 Pathway of Carbon into Primary Producer Air Root NA Bio1/Bio2 (n=63) 0ther + Bio2 (n=40) Concept 2: Plants uptake CO 2  2 (1) = 8.89, p < 0.05

So What?

Problem sets about major concepts » Diagnostic re: what students understand/misconceptions » » » » » Methods; parallel to process in disciplinary research Learn what prior knowledge students brought to course Learned what knowledge students’ gained Unveil new misconceptions Influenced what we taught, how we taught it

So What?

(2) Curricular changes » Bacteria/Archaea metabolism - often omitted » Primary production - models in lab » Source/Sink and carbon flux » ‘Spiral’ major concepts - over/over/over » Use of CTOOLS (concept mapping java applet ctools.msu.edu)