A fourth grade class designed a controlled experiment, under the guidance
of their science cluster teacher, to compare and contrast the structures
and growth of six different varieties of bean plants during the plants’
life cycles. The students were asked to select two of the varieties and
to determine which of the two they would want to plant, if they were farmers,
and why. Each student was given an individual opportunity during science
class to observe the plants by using magnifying lenses and to take measurements
using string and rulers. Each student kept a log of findings and wrote a
conclusion based on them.
| This sample of student work was produced under the following
conditions: |
| alone |
in a group |
| in class |
as homework |
| with teacher feedback |
with peer feedback |
| timed |
opportunity for revision |
|
|
 |
 b
Life Sciences Concepts: The student
produces evidence that demonstrates understanding of life cycles of
organisms…and that all plants and animals have life cycles.
 The student began
the documentation of the bean plant life cycle with a drawing of the
germination of five seeds.
Understanding of a subsequent stage in the bean plant life cycle is
demonstrated in the entry for 9/25/98 in both the labeled diagram
and in the wording: “Three [of the initial five seeds] are now
seedlings.”
Evidence of understanding of other life cycle stages is found in the
conclusion. The student notes that the bush bean plants produced more
flowers and pods than the kidney bean plants did. The student clearly
understands that pods produce beans. The student also uses the term
“life cycle” in a correct comparison based on observations. |
 |
 b
Scientific Thinking: The
student uses concepts from Science Standards 1 to 4 to explain a variety
of observations and phenomena.
The student’s conclusion applies concepts from b.
 a
Scientific Tools and Technologies: The
student uses…tools (such as rulers,…magnifiers) to gather
data and extend the senses.
In the 11/2/98 entry, the measurements for pod length and width are
recorded next to a diagram of the bean pods. The student used a metric
ruler to measure lengths and widths of pods.
 The student measured
and recorded plant height and circumference using a metric ruler and
string.
 The
student used a magnifying lens to examine the structures of the flowers
and the emergent pods. |
 |
 a
Scientific Communication:
The student represents data and results in multiple ways, such as…drawings,
diagrams, and artwork, and…technical writing.
The student used a labeled drawing to communicate measurement of the
bean pods and used two sentences to convey these observations.
 In all of the
entries from 10/5/98 through 10/27/98, the student used labeled drawings
in brief log entries to illustrate understanding of differences between
compound and simple leaves and to note the development of flowers
and pods.
b
Scientific Communication: The
student uses facts to support conclusions.
 
Observations and
data recorded in the log kept over the course of the experiment support
the conclusion. |
 |
The student observed that the bush beans produced the greater number
of flowers. To arrive at the conclusion, the student combined this
fact with an understanding, explicitly indicated in the conclusion,
that bean flowers produce bean pods and pods produce seeds.
c
Scientific Communication: The
student communicates in a form suited to the purpose and the audience,
such as writing instructions that others can follow.
 The work includes
a step-by-step procedure that would allow for replication of the experiment
by another elementary student.
 a
Scientific Investigation:
The student demonstrates scientific competence by…an experiment,
such as conducting a fair test. |
 |
 The procedure
indicates that all factors were kept the same in the germination and
growth of the two kinds of bean plants. In the conclusion, the student
cites observations of differences in the relative hardiness of the
plants that resulted from the procedure. |
|
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