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1.  Studying Human Disease Genes in Caenorhabditis elegans: A Molecular Genetics Laboratory Project 
CBE Life Sciences Education  2012;11(2):165-179.
Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether Caenorhabditis elegans can be a useful model system for studying genes associated with human disease. In a large-enrollment, sophomore-level laboratory course, groups of three to four students were assigned a gene associated with either breast cancer (brc-1), Wilson disease (cua-1), ovarian dysgenesis (fshr-1), or colon cancer (mlh-1). Students compared observable phenotypes of wild-type C. elegans and C. elegans with a homozygous deletion in the assigned gene. They confirmed the genetic deletion with nested polymerase chain reaction and performed a bioinformatics analysis to predict how the deletion would affect the encoded mRNA and protein. Students also performed RNA interference (RNAi) against their assigned gene and evaluated whether RNAi caused a phenotype similar to that of the genetic deletion. As a capstone activity, students prepared scientific posters in which they presented their data, evaluated whether C. elegans was a useful model system for studying their assigned genes, and proposed future directions. Assessment showed gains in understanding genotype versus phenotype, RNAi, common bioinformatics tools, and the utility of model organisms.
PMCID: PMC3366902  PMID: 22665589
2.  Tools and Tips for Teachers 
CBE Life Sciences Education  2011;10(2):146-148.
PMCID: PMC3105920
3.  Facilitating Learning in Large Lecture Classes: Testing the “Teaching Team” Approach to Peer Learning 
CBE Life Sciences Education  2010;9(4):489-503.
We tested the effect of voluntary peer-facilitated study groups on student learning in large introductory biology lecture classes. The peer facilitators (preceptors) were trained as part of a Teaching Team (faculty, graduate assistants, and preceptors) by faculty and Learning Center staff. Each preceptor offered one weekly study group to all students in the class. All individual study groups were similar in that they applied active-learning strategies to the class material, but they differed in the actual topics or questions discussed, which were chosen by the individual study groups. Study group participation was correlated with reduced failing grades and course dropout rates in both semesters, and participants scored better on the final exam and earned higher course grades than nonparticipants. In the spring semester the higher scores were clearly due to a significant study group effect beyond ability (grade point average). In contrast, the fall study groups had a small but nonsignificant effect after accounting for student ability. We discuss the differences between the two semesters and offer suggestions on how to implement teaching teams to optimize learning outcomes, including student feedback on study groups.
PMCID: PMC2995767  PMID: 21123696
4.  Nothing in Evolution Makes Sense Except in the Light of DNA 
CBE Life Sciences Education  2010;9(2):87-97.
Natural selection is one of the most important concepts for biology students to understand, but students frequently have misconceptions regarding how natural selection operates. Many of these misconceptions, such as a belief in “Lamarckian” evolution, are based on a misunderstanding of inheritance. In this essay, we argue that evolution instructors should clarify the genetic basis of natural selection by discussing examples of DNA sequences that affect fitness. Such examples are useful for showing how natural selection works, for establishing connections between genetics and evolution, and for creating cognitive conflict within students having misconceptions. We describe several examples of genes that instructors might use during lectures, and present preliminary evidence from our classroom that an evolution curriculum rich in DNA sequences is effective at reducing student misconceptions of natural selection.
PMCID: PMC2879385  PMID: 20516354
5.  Rethinking Exams and Letter Grades: How Much Can Teachers Delegate to Students? 
CBE— Life Sciences Education  2006;5(3):270-280.
In this article we report a 3-yr study of a large-enrollment Cell Biology course focused on developing student skill in scientific reasoning and data interpretation. Specifically, the study tested the hypothesis that converting the role of exams from summative grading devices to formative tools would increase student success in acquiring those skills. Traditional midterm examinations were replaced by weekly assessments administered under test-like conditions and followed immediately by extensive self, peer, and instructor feedback. Course grades were criterion based and derived using data from the final exam. To alleviate anxiety associated with a single grading instrument, students were given the option of informing the grading process with evidence from weekly assessments. A comparative analysis was conducted to determine the impact of these design changes on both performance and measures of student affect. Results at the end of each year were used to inform modifications to the course in subsequent years. Significant improvements in student performance and attitudes were observed as refinements were implemented. The findings from this study emphasized the importance of prolonging student opportunity and motivation to improve by delaying grade decisions, providing frequent and immediate performance feedback, and designing that feedback to be maximally formative and minimally punitive.
PMCID: PMC1618686  PMID: 17012219

Results 1-5 (5)