Linda Heidenrich
SED625SC
Current Event #1: Effect of Bead and Illustrations Models on High School
Students’ Achievement in Molecular Genetics
This study was completed in Tel Aviv, Israel with three comparable groups of
high school students, specifically 11th and 12th graders. The 258 students were broken
into three groups: a control group (116 students), an illustrations group (71 students) and
a bead model group (71 students). All three groups were taught with traditional methods,
including teacher lecture on the blackboard incorporating transparency use as well as
reading and answering questions from the textbook. The illustrations group and the bead
group had additional instruction with guiding questions related to their activity. This
study focused on improving knowledge of three areas of molecular genetics: the structure
of DNA and RNA, molecular process such as replication, transcription and translation,
and the conceptual relationships between genetic code and the phenotypic product.
The experimental design for this study was respectable because the researchers
referenced, and built upon, previous studies to design an effective measure of students’
success with genetics.
For example, the researchers referenced several studies that
showed the significant improvement in retention of complex scientific data when
“pedagogical, analogical models” were used (502).
Based on these studies, the
researchers designed the bead model, an analogical physical model, and the illustrations
model, an analogical visual model, for use in this study (503).
In addition, the
researchers designed three measures of knowledge to accurate determine student success.
Their study used a multiple choice written questionnaire, an open-ended written
questionnaire and an open-ended verbal questionnaire (509). The researchers developed
these questionnaires with the assistance of two science education experts from
universities and colleges as well as two high school biology teachers. The questionnaires
were then piloted with a group of Israeli students and their feedback was taken into
account and the questionnaires were revised prior to the start of the study (509). The
rubric used in scoring of the questionnaires was also evaluated by university and high
school teachers not associated with the study (510).
The researchers also conducted a
pretest to ensure the three groups were equivalent in their base knowledge (509). Using a
variety of testing instruments, the researchers were able to conclude with regard to all
three areas being studied, the general trend showed students with exposure to the bead
model had the highest level of success and the control group students had the least
success. In addition, for several areas of testing, a large proportion (25%-30%) of the
control group students failed to attempt to the answer the question whereas the proportion
of the test groups failing to answer the question was usually less than 10% (516). This
data allowed the researchers also to conclude students with exposure to models, visual or
actual, have a greater comfort with complex scientific ideas (518).
This study is valuable to me because I teach these complex molecular concepts
using interactive visuals (drawings, picture to color code and illustrations to label) and
models while several of my colleagues teach these concepts using the traditional methods
of lecture, transparency use and workbook exercises. This discrepancy in teaching styles
is seen during department meetings when our data from district wide benchmarks is
compared. My SDAIE students score equally as well as equivalent level students in my
colleagues’ classes. Biology offers nearly as many terms as a foreign language course
requiring educators to find ways to bring the words off the page; models and illustrations
allow educators to illuminate critical concepts and allow students to be successful.