Running head: Three Formative Assessments
Three Formative Assessments About Matter and Energy Conversions in High School Biology
Matthew P. Sheick
Michigan State University
April 21, 2013
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Three Formative Assessments About Matter and Energy Conversions in High School Biology
Draft Formative Assessment
Topic Description
The unit that the Biology class is currently beginning is called Matter and Energy in
Ecosystems. This unit focuses on energy transformations, both at the cellular and ecosystem
level, building upon an earlier unit about cell energetics (photosynthesis and respiration).
Students should be able to explain how plants convert energy in sunlight into chemical energy
stored in glucose during photosynthesis and how both plants and animals use that chemical
energy through cellular respiration. Reading literature for this assignment revealed that students
often have a number of misconceptions about photosynthesis and respiration in general. These
include having difficulty explaining how living organisms gain and lose mass through the
processes of photosynthesis and respiration (Eisen & Stavy, 1988).
Targeted Learning Goals:
For the targeted lesson sequence as it pertains to this assignment, the learning goals will
be for students to explain how energy is transferred from the sun to organisms to provide energy
for all life forms to exist. To successfully do this, they will need to be able to describe the energy
conversions at the cellular and ecosystem level (students have already studied photosynthesis and
respiration earlier in the year) and use this knowledge to describe how living organisms gain and
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lose mass through photosynthesis and respiration. These goals are adapted from part of Unit 7 in
the Michigan High School Content Expectations for Biology Companion Document.
Formative Assessment Task(s) and Rationale
The first formative assessment I will give as we begin this lesson sequence will be to
have students draw a picture representation of the flow of energy through an ecosystem. Their
drawing must include the Sun and at least 5 different living things. A drawing assignment such
as this may allow students who have difficulty expressing ideas in words (English Language
Learners for instance) opportunity to demonstrate their understanding (McNair, 2004). From an
instructional standpoint, the goal of this assessment is to see if students are able to describe
(through a picture) the concept of energy transfer through an ecosystem. I expect that most
students will include some type of plant in their drawing. This may indicate an proficient
understanding of the process of photosynthesis or they may simply know that “energy” from the
Sun “goes to” plants.
As I’ve discovered through numerous course readings (White & Gunstone, 1992,
Popham, 2011), it is essential to offer different forms of assessment to provide a more
comprehensive measure of student understanding. In order to determine how well students
understand how plants gain and lose mass, I will lead students through a predict-observe-explain
lesson called “Plant Growth Puzzle” (Serendip/BrynMawr, n.d.). The idea of this activity is to
help students understand that mass in plants is gained through photosynthesis (primarily by using
atoms of carbon from carbon dioxide and building glucose) and not pulling in mass from the soil
or getting mass directly from the sunlight itself. For the activity, students will be told that 1.5
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grams of seeds were placed into three separate Petri dishes. One dish was placed in the sunlight
but never watered. The second dish was placed in the sunlight and the seeds were watered. The
third Petri dish was watered and placed in the darkness. For each of the conditions, students will
be asked to make a prediction about plant growth and whether the mass will increase, decrease or
stay the same after 10 days (and subsequent drying). Students will have to justify this prediction
(the second page of the “Plant Growth Puzzle” sheet. This prediction stage is crucial and students
will need to write down their prediction and their justifications (White & Gunstone, 1992). I
anticipate that most students will think that the seeds in the sun and water will grow, but I think
that many students will say that the seeds in the dark with water will not grow. Asking questions
during this prediction stage will be crucial, for instance, “Why do you think that the seeds in the
dark with water will (or will not) grow?
Next, students will be shown picture results after 10 days (Appendix A). This will serve
as the observation stage. Finally, students will have to compare their predictions with the actual
results. Regardless if students are correct or not, students will be asked to explain why the seeds
in the light with water grew and gained mass and why the seeds in the dark grew but lost mass.
The third formative assessment task will take place after the “Plant Growth Puzzle.” I
plan to project a data table (I’m currently trying to improve the ability of my students to glean
information from tables and graphs) showing the approximate elemental composition of wood by
number of atoms and by mass. Students will be instructed to examine the data table and thinkpair-share their responses to the question “Where does the carbon in wood come from?” The
rationale for this type of activity is to allow students a chance to think on their own, share their
idea with a classmate and report out to the class. From personal experience, I know that many
students are verbally engaged in the class but hesitate to write (due to lack of motivation, low
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confidence, etc). While circulating through the room during this time, I will be able to hear
students’ reasoning about the origin of the carbon atoms in trees. I plan to specifically listen for
any existing misconceptions (carbon is getting sucked up by roots for instance). By this time,
students should understand and describe how the mass of a plant (tree) is obtained mainly
through the formation of glucose (using atmospheric carbon dioxide) during photosynthesis.
Scoring Guide for Analyzing Students’ Responses to the Formative Assessment Task(s)
Develop scoring guide(s) to evaluate student responses to your task(s). These scoring
guides should help you to assess where students are making progress and where they have
challenges with the content. These should be general scoring guides for each task that show how
you evaluated student responses.
Scoring Guide: First Assessment (Energy Transformation in Ecosystems Drawing)
For this assessment, I am really looking to see how students diagram energy in an
ecosystem. This will be done as a Do Now activity in class, and as such, students will be
encouraged to put out any ideas they have and they know they will earn full credit for
completing the assignment, even if their responses may not be scientifically accurate. A simple
rubric for this assessment is shown below in Figure 1.
Figure 1. Scoring Guide to Energy Transformation Drawing
Do the living things
include plants AND
animals?
Are energy
conversions shown
by arrows and
indicating flow of
energy (as opposed
to showing what
eats what)?
Does the student
include living things
of different trophic
levels (decomposers
for instance)?
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Yes
No
Scoring Guide: Second Assessment (Plant Growth Puzzle)
This assessment will be scored primarily on student’s justification of their predictions.
See Figure 2 below.
Figure 2. Scoring Guide to Plant Growth Puzzle
Seeds in the dark
grow?
Seeds in the dark
grow?
What ideas are
brought forth in
their justifications?
Yes
No
Scoring Guide: Third Assessment (Where does a tree’s mass come from?)
By the time this third assessment is introduced, students should have a solid
understanding that the mass of a tree primarily originates from carbon atoms taken from carbon
dioxide during photosynthesis. The glucose produced during this process is used as a building
block for larger molecules making up wood. See Figure 3 below.
Figure 3. Scoring Guide to Tree Mass Explanation
Do they include
photosynthesis?
Do they specify that
mass is mostly
carbon originating
from atmospheric
carbon dioxide?
What
misconceptions do
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students still hold?
Yes
No
Analysis of Student work
1. First assessment: A variety of ideas were generated in the first formative assessment.
When examining student work using the scoring guide in Figure 1 above, most all
students included plants and animals. Only one student in my class showed light energy
from the sun moving directly into animals (this student drew lines from the Sun directly
to five different living things). A few students (n=3) included some form of decomposer
in their drawing (“mushroom” or “fungi”).
Most of my students have grown up in a rural area and at least have a passing
relationship with nature. Because of this, they demonstrated a fairly solid understanding
that energy moves from the sun to plants (some students even used the word producers)
to animals. I only had to focus on a few issues (arrows represent flow of energy, rather
than the eating of something) as we progressed to constructing food webs (done in
another activity not included in this assignment).
2. Second assessment: The second assessment examined whether students connect the gain
in mass in plants to photosynthesis. My hope was that students would transfer what they
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knew about food and energy webs (specifically the integral role of producers) to the Plant
Growth Puzzle. This was a little tricky because the fact that sunlight is needed for plants
to do photosynthesis has been beaten into their heads since middle school. As seeds
germinate though, they do not receive sunlight and are therefore not yet doing
photosynthesis, instead, they rely on the stored energy in the seed. This tripped up a
number of students. Initally, the class had mixed responses to the question “Which
process can result in increased mass for a plant?” (question number 5a). Further probing
revealed that we still had not addressed the commonly held misconception that a plant
pulls in nutrients to build its mass through its roots. I hoped that formative assessment
number 3 would help address this issue specifically.
3. Final assessment: For the third assessment, students responded to the question, “Where
does the carbon in wood come from?” The vast majority of students included
photosynthesis in their answer (several students simply said photosynthesis). About a
third of the students indicated that the carbon originated from the atmospheric carbon
dioxide. A couple of students did not seem to connect this question to energy
transformations in photosynthesis (“The mass of a tree comes from the water, sun [sic]
and nutrients absorbed by the tree.”) Either this student had difficulty reading the
tabulated data displaying the composition of wood or the student was not swayed by the
lesson sequence. This is still a challenging concept for the general population to
understand (adults included). For this student, I revisited the Plant Growth Puzzle data,
showing that there was no soil and that any carbon in the plant itself HAD to come into
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that plant through the leaves (assuming there is no additives to the water). She seemed to
follow this line of thinking.
Final Written Report
Introduction
During this assignment, I was teaching the topic of energy and matter transformations in the unit
Energy and Matter in Ecosystems. This is a topic that students seem to handle relatively easily at
a superficial level because it builds on what many of them learned in middle school about
ecosystems (food chains, producers vs consumers, etc). However, good assessments can reveal
that many students hold common misconceptions about the flow of matter and energy both at the
cellular level and at the ecosystem level (Eisen & Stavy, 1988). Specifically, students often
struggle with explaining how living things gain and lose mass through photosynthesis and
respiration.
The first formative assessment I gave was to draw a picture representation of the flow of
energy through an ecosystem. Their drawing must have included the Sun and at least 5 different
living things. A couple of sample drawings are shown in Appendix B. The second assessment
was their justification of their predictions during the Plant Growth Puzzle. An example of student
work is found in Appendix C. The third assessment was their responses to the question “Where
does the carbon in wood come from?” I know that all students would not be able to describe
where the “mass” of a tree came from, but by relating it to carbon specifically, I hoped to reveal
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to them that the carbon mass must originate as atmospheric carbon dioxide. See Appendix D for
an example of a student response.
Analysis of Student Learning
Overall, students met the expectations that I had for them (as students often do). I used the
student drawings of energy moving through an ecosystem to begin a conversation about where
the energy in our ecosystem originates. Students immediately were able to say that it came from
the Sun, but were less certain about how other living things accessed that energy. This provided a
good means of revisiting photosynthesis, highlighting not only the energy conversions (light to
chemical) but also the reshuffling of atoms, specifically carbon atoms. By experiencing the POE
Plant Growth Puzzle activity, students were able to look at biomass data and connect back to the
idea of photosynthesis being a means to build mass in a plant. Students did a good job of
verbally explaining this to me in the classroom, but had more difficulty explaining it on paper.
For instance, a number of students said that sunlight is needed for a plant to “grow healthy” (see
number 7, Appendix C).
Reflections on Teaching
Address the following questions:
1. How were the formative assessments able to provide you feedback on instruction? The
formative assessments provided me useful feedback in terms of student responses.
Specifically, the responses that classroom discussion generated were particularly
beneficial for me as I planned instruction. Unfortunately, that did not always find its way
into the written student work. I will need to revisit the format of some of the assessments
(namely the Plant Growth Puzzle) to better address this issue. Without these formative
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assessments, I would not know that students still hold the misconception that plants
obtain their mass through absorbing “stuff” through their roots.
2. Were there ideas that formative assessment did not provide you feedback on as expected?
If so, what were they and how would you change the formative assessment to better
assess those ideas? The formative assessments that I used for this assignment did not
probe student understanding on mass loss. These assessments only focused on
photosynthesis and the gain of mass and therefore did not provide me with much insight
into this idea. From here, I could move into respiration as a means to lose mass (even
when humans “lose weight”). A formative assessment might be to ask students where
Jared’s weight went (from Subway).
3. How would you modify instruction based on your results? I found myself moving slower
through the unit when focusing on these formative assessments and the student work
analysis. An obvious modification would be that my results caused me to slow down the
pace of the lesson sequence. I anticipated that this entire lesson sequence (these formative
assessments were but a part of that) would take about 3 classes. However, it took nearly 5
class periods due to the discussions generated during the Plant Growth Puzzle and the
Carbon in Wood question.
Conclusion
In summary, I learned that in order to get a good pulse on student thought, it takes a variety of
assessments issued at various intervals. This allows the teacher to gauge their instruction and
alter it if needed and also provide students a chance to push their thinking. I learned that students
hold more misconceptions than I originally expected about energy transformations and how they
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relate to mass gain and loss in living things. Overall, this process was fairly tedious and difficult
to do on a daily basis (particularly looking that deeply at student work). However, the value in
analyzing student work, planning various formative assessments and using them to shape my
teaching has been emphasized.
References
Eisen Y, Stavy R. (1988). Students' understanding of photosynthesis. Am Biol Teach; 50: 208–
212.
McNair, S. (2004). “A” is for assessment. Science and children; Sep 2004; 42, 1; ProQuest
Research Library pg. 24
Popham, W. J. (2011). Classroom assessment: What teachers need to know. 6th ed. Pearson,
Boston, MA.
Serendip/Bryn Mawr. (n.d.). Retrieved April 21, 2013 from the Serendip site:
http://serendip.brynmawr.edu/exchange/bioactivities/plantgrowth
White, Gunstone (1992). Probing for understanding. Ch 3.
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Appendix A
Plant Growth Puzzle Observed Results
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Appendix B
Mass-Energy Through Ecosystem Drawings
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(Appendix B Continued)
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Appendix C
Plant Growth Puzzle
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(Appendix C continued)
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Appendix D
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Where does the carbon in wood come from?
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