The nature of science (NOS) is an often neglected part of science teaching, yet it provides a vital background for students, detailing how science and scientists work and how scientific knowledge is created, validated, and influenced. Here, I review the concept of NOS and some of the challenges to its inclusion in science classes. In addition, I outline proposals, including those in the Next Generation Science Standards, for those aspects of NOS that should be featured in science classes. Finally, I discuss distinctions in NOS specific to the science of biology and conclude with some thoughts on how NOS can be incorporated into science instruction.

Students often have difficulty understanding inheritance patterns and issues associated with the nature of science as a process. To help address these issues, we developed a unit plan based on Gregor Mendel's well-known research on inheritance patterns among pea plants. The unit introduces students to Mendel's background and the questions he sought to address. Students then conduct their own investigation, using Virtual Genetics Lab II (VGLII) software to attempt to confirm Mendel's results. In the course of completing their investigations, students learn about alternative inheritance patterns to Mendelian genetics. The unit was created in the context of a college introductory biology course but could be implemented in a high school course.

Helping students understand and generate appropriate hypotheses and test their subsequent predictions — in science in general and biology in particular — should be at the core of teaching the nature of science. However, there is much confusion among students and teachers about the difference between hypotheses and predictions. Here, I present evidence of the problem and describe steps that scientists actually follow when employing scientific reasoning strategies. This is followed by a proposed solution for helping students effectively explore this important aspect of the nature of science.

Intelligent Design (ID) proposes that biological species were created by an intelligent Designer, and not by evolution. ID's proponents insist that it is as valid a theory of how biological organisms and species came into existence as evolution by natural selection. They insist, therefore, that ID be taught as science in public schools. These claims were defeated in the Kitzmiller case. However, ID's proponents are still influential and cannot be considered a spent force. The question addressed here is whether ID's claim of scientific legitimacy is reinforced by quantified results. That is, do they have any data, or do they just argue? The ID articles that I analyzed claimed to present real science, but they rarely referred to data and never tested a hypothesis. Argumentation, however, was frequent. By contrast, peer-reviewed articles by evolutionary biologists rarely argued but referred frequently to data. The results were statistically significant. These findings negate claims by ID proponents that their articles report rigorous scientific research. Teachers will find this article helpful in defending evolution, distinguishing science from non-science, and discussing the weaknesses of ID.

Acorn ants (genus Temnothorax) are a powerful model organism for illustrating the variety of interactions in an ecosystem. We developed five teaching units with acorn ants as the exemplary insect. The aim of this study was to provide a quantitative and qualitative analysis of secondary school students' attitudes before and after teaching units. Students (N = 459) from 22 classes participated in the study. Students' attitudes were measured using a two-stage test design. We investigated the influence of class level, gender, teaching units, and time period of participation on students' attitudes. Additionally, we surveyed a subsample of students on their learning enjoyment in 10-minute interviews. The findings suggest that students' previous investigations with insects in science classes had been few. The results indicate an influence of gender, time period, and the autonomous keeping of ants on attitudes toward the social insects. Although no changes in attitudes were observed for students of lower and higher secondary school, students at the intermediate level had slightly higher-attitude scores on the posttest than on the pretest. The majority of students evaluated teaching units positively. Our findings suggest that ant research may offer new opportunities for directing students' attention to native woodland inhabitants.

The importance of a robust undergraduate research experience has been demonstrated time and again. However, too few undergraduates engage in genuine research and leverage this opportunity. Here, I present a laboratory course in cell and molecular biology that is designed to mimic a true research project. Students work through a 10-step experimental design culminating in the construction, expression, and visualization of microtubules fused to green fluorescent protein in baker's yeast. The steps of this project include the isolation of the tubulin gene from yeast genomic DNA, the cloning of that gene into an expression vector, the amplification of this plasmid in E. coli, and the expression of fluorescent tubulin in yeast. Controls and validation steps are embedded throughout the project, as they would be in a genuine research project. This laboratory course more closely resembles a one-semester undergraduate research experience than a typical lab course. However, because this course reaches a much larger number of students compared with undergraduate research opportunities, it provides students with a valuable research experience that remains confined to the scheduled time block of a typical lab course. In this way, many of the benefits of research are experienced by a large number of undergraduates.

Repeatability underpins a basic assumption in science which students must learn in order to evaluate others' research findings as well as to communicate the results of their own research. By attempting to repeat the methods of published studies, students learn the importance of clear written communication, while at the same time developing research skills. I describe three examples of published field studies that can be used as the basis for course exercises on the repeatability of methodology, as well as field sampling techniques, all grounded in the overall topic of environmental change. Two of the exercises returned students to the exact location of the past research that they had previously read from the primary literature, making it possible to clarify the difference between reproducibility and repeatability in field-based research. When student-collected data differed from published results, students explored, through both post-project discussions and written work, factors that could explain this variation, including methodology, ecological succession, and climate change. Assessments and student comments on course evaluations showed that these exercises have a positive impact on students' communication skills and engagement with the scientific process.

There is increasing emphasis on teaching science as a way of knowing about the natural world. Central to this effort is fostering an understanding of the differences between facts, laws, and theories. Among these, the concept of a scientific theory is typically the most challenging to teach. Many students have a preconceived, colloquial notion of theories as purely speculative explanations that can be legitimately assessed by cursory examination. The exercise presented here engages students in the process of theory development and testing, thus clarifying the central role that theories play in science.

Surveys have shown that a proportion of the American public accepts pseudoscientific claims as scientific facts. The critical evaluation of these claims via classroom discussion about pseudoscience is important because instructors and students cannot test every pseudoscientific claim. Instructors can provide a framework to use in evaluating such claims both inside and outside the classroom, arming students with knowledge. I describe an activity that provides both an example of a pseudoscientific claim — astrology — and a framework for classroom discussion of pseudoscience as students work in groups to experimentally test predictions of horoscopes. The activity is appropriate for freshman college students in an online or classroom biology laboratory and can be adapted for high school students.

I modified the classic Mystery Tube activity to teach not only the nature of science but also the nature of what is not science. In order for evidence and logic to be effective tools for teaching evolution, instructors may first benefit from giving students a tangible reason to set aside any prior nonscientific ideas they bring to the classroom. This activity helps instructors intentionally delineate scientific from nonscientific hypotheses, providing a clear and logical reason for teaching evolutionary theory, but not metaphysical ideas, in the science classroom.