The Astrobiology in Secondary Classrooms (ASC) Curriculum: Focusing Upon Diverse Students and Teachers

Introduction

T he intent of the Astrobiology in Secondary Classrooms (ASC) project is to establish a successful model for creating the scientists of tomorrow by bringing powerful technology tools and current scientific data into an interdisciplinary curriculum focused on reaching all students. Goals for students participating in the ASC curriculum in their classrooms included:

The ASC curriculum tackles many of the current problems in science education by addressing curriculum issues as well as minimizing classroom limitations that affect science instruction, particularly in classrooms containing high numbers of students underrepresented in science careers. Many science curricula, including textbooks, lack connections among different academic disciplines and do not provide students with a coherent framework for both science literacy and content knowledge. The ASC modules have been developed by using research-based teaching strategies designed to diminish achievement gaps and increase the participation of underrepresented STEM groups. The ASC curriculum development and research program brought together educators and scientists to expand and modify an existing astrobiology curriculum and conduct educational research to determine the appropriateness of these materials for diverse student populations. The redesign of the curriculum concentrated on two areas: (a) strengthening the alignment of ASC with standards for effective pedagogy and student outcomes with diverse student groups proposed as a part of the Center for Research on Education, Diversity, and Excellence, 2002 (CREDE), project (Tharp et al., 2000; Tharp et al., 2003), and (b) increasing the use of data sets provided by research scientists in the field of astrobiology.

The ASC project began in 2003 with a team of university faculty from minority-serving institutions and teachers selected by members of the Minority Institution Astrobiology Collaborative (MIAC). Working with scientists at the Goddard Center for Astrobiology, the team developed the ASC curriculum framework. Now, through this network of minority-serving institutions, the ASC staff endeavors to enable middle and high school teachers across the United States to include astrobiology-related activities in their classrooms. Major partners during the field-testing phase of the materials were sites designated as NASA Science, Engineering, Mathematics, and Aerospace Academies (SEMAA). Partnerships with SEMAA programs and other minority-serving locations allow for a focus on diversity when field-testing and developing the ASC curriculum in both formal and informal educational settings. There were field-testing sites in eight different locations, where more than 80 percent of the students are members of the Native American, African American, or Hispanic American communities.

Content Framework Based on Research

The developed modules are based on recent research strategies designed to diminish achievement gaps and improve the participation of underrepresented groups in STEM activities. Research supports the use of astrobiology as a framework for increasing science literacy (Carrapico et al., 2001; Astrobiology Design Project Team, 2002; Staley, 2003; Rodrigues and Carrapico, 2005; Tang, 2005; Slater, 2006) and indicates that cultural awareness is key for successful, engaging science teaching (Aikenhead, 2001; Lynch et al., 2005; Lee and Luykx, 2006). Our design rationale has been sculpted by key educational theorists such as John Bransford and his work on how people learn (Bransford et al., 1999; Donovan and Bransford, 2005), the standards proposed by the CREDE project that characterize the dynamics of learning in diverse cultures, and the backward design principles of Wiggins and McTighe (1998). A strategy that has been stressed in the previous development is the integration of differentiated instruction and assessment to assist teachers to meet the needs of students with varying abilities (Tomlinson and McTighe, 2006). The modules incorporate flexible goals, methods, materials, and assessments that accommodate learner differences as part of an effort to comply with the Universal Design for Learning (Center for Applied Special Technology, 2012).

The Continuing Need for High-Quality Science Programs Targeting Minority Students

Despite many efforts to eliminate the achievement gap between mainstream and non-mainstream students, an achievement gap continues to be reported between these two student groups, especially in the sciences at the high school level. This dichotomy in student progress is outlined as a part of the 2005 National Assessment of Educational Progress (Grigg et al., 2006). There are several possible reasons non-mainstream students have continued to lag behind mainstream students in national and local science assessments. Possible conditions that may contribute to this achievement gap include the high incidence of less skilled and experienced teachers in school districts with a high population of non-mainstream students, resulting in over-reliance on textbooks that are likely to be poorly written, especially by the standards set forth by the American Association for the Advancement of Science (AAAS) and Project 2061 (Roseman et al., 1997). This combination of poorly constructed textbooks and other curricular materials with teachers unable to compensate for the difference in quality through pedagogical skills is most apt to affect diverse learners (National Commission on Science and Mathematics Teaching for the 21^st Century, 2000). Deficits in curriculum and instruction stratify student achievement and are further compounded by the inability of the educational system to respond in an effective and timely manner to the changing diversity of the K-12 student population (Lynch et al., 2005). Teachers of diverse student groups are therefore most in need of effective, engaging science curricula. These same teachers are also in need of support in teaching these curricula, in the form of ongoing professional development and implementation support from the curriculum developers. During the ASC Research and Development project we intend to provide both the curriculum and the implementation support necessary for the success of the teachers in diverse classroom settings.

The Importance of Culture in Effective Science Education

The Journal of Research in Science Teaching published an entire issue devoted to the importance of culture and language in science teaching. To support diverse groups of students in science literacy, as well as inspire the scientists and engineers of tomorrow, educational researchers investigating effective science curricula and instructional practices need to combine findings while synthesizing new ideas to effectively reach these non-mainstream students through well-designed instructional programs. There is limited credible, repeatable research on effective instructional programs for diverse groups of students, particularly in the areas of science and mathematics (Lee and Luykx, 2006). However, Lee and Luykx (2006) reviewed research findings and current trends in science education for diverse student populations while providing a research agenda for future endeavors. Factors affecting effective science education and overall science literacy include cultural variances in students' worldview, differences in the communication and interaction patterns of non-mainstream students, and differing abilities to negotiate cultural transitions between home and school settings.

In response to these diverse groups of students, some curriculum materials have been modified to be more culturally relevant, for example, with Hispanic and African American students (Lee et al., 2005) or with Native American students (Aikenhead, 2001). These studies both reported positive results and further confirmed the positive outcomes of culturally meaningful materials on science achievement and attitudes of non-mainstream students seen by Matthews and Smith (1994). As each cultural group is vastly different, even between groups of the same overall cultural identity but in different geographic locations (for example, Hispanic Americans on the eastern U.S. coast compared to those living on the western U.S. coast), modifying each activity of a nationally disseminated curriculum is not as practical as encouraging the use of pedagogical practices that tailor the instructional environment to best suit the needs of diverse groups as a whole.

Lynch and colleagues (2005) concluded that studying theoretical perspectives for understanding how language and culture affect science learning while exposing advantages and impediments brought by current practices in science education is essential (e.g., Aikenhead and Jegede, 1999; Gilbert and Yerrick, 2001; Moje, 2001; Solano-Flores and Nelson-Barber, 2001). By applying these theoretical perspectives to the curriculum design process, along with other educational best practices, several groups have successfully produced curricula that are effective with underrepresented students, such as the LeTUS project (Rivet and Krajcik, 2004) and the “Kids as Global Scientists” program (Songer et al., 2002; Lee and Songer, 2003; Songer et al., 2003). We used high-quality programs such as these as exemplars for the ASC Research and Development Project.

The ASC development team combined both cultural relevancy and instructional strategies into the ASC curriculum to best meet the needs of diverse student groups across the United States. By considering these differences among students when designing science curricula, we designed a culturally aware science curricula containing opportunities for expression of the cultural diversity contained in these classrooms.

Astrobiology Is an Ideal Medium to Reach Students Struggling in Science

The Astrobiology in the Secondary Classrooms (ASC) curriculum allows students and teachers to see the connections among concepts in physics, biology, chemistry, geoscience, astronomy, mathematics, and ethics. By connecting these concepts, students gain a better understanding of the nature of science through researching questions whose answers are not yet definitive, which allows students to create moments of reflection, questioning, and creativity (Carrapiço et al., 2001). Building upon the existing body of knowledge in astrobiology science education as well as research on effective pedagogy for diverse groups of students, ASC combines the findings of several highly respected science researchers (Billings et al., 2006) and educational research groups in an effort to reach the students who are in need of quality science programs the most.

Astrobiology (formerly termed exobiology) has a proven track record for increasing the science literacy of college-age students with nonscience majors (Tang, 2005), as well as honors students at the collegiate level (Danly, 2004). We hope to replicate these results with the ASC curriculum at the high school level by including topics in astrobiology that have been studied for their potential to capture student interest (Slater, 2006) as well as those that challenge student beliefs in a manner that provokes scientific reasoning (Offerdahl et al., 2002). The modules of ASC have been designed and arranged in a manner consistent with the literature on logical progressions for astrobiology curricula, such as those outlined by the Astrobiology Project Design Team (2002) and Rodrigues and Carrapiço (2005).

Currently available curricula incorporating a theme of astrobiology are compatible with, yet vastly different in nature from, the ASC curriculum. There are many curricula available for elementary and middle school grades, especially on the Internet and through NASA-sponsored websites (e.g., AstroVenture). At the high-school level, two main curricula are currently available in the United States. One of the resources available for purchase as an astrobiology curriculum is Voyages Through Time. This product is a “year-long, integrated science curriculum for ninth or tenth grade, based on the theme of evolution and delivered on CD-ROM” (SETI Institute, 2012). The ASC curriculum contains a different emphasis by focusing upon the research of astrobiologists and their search for clues pertaining to life in the universe. The other main astrobiology curriculum currently available was developed by Technical Education Research Centers (TERC). The TERC astrobiology curriculum is a yearlong inquiry-based curriculum for middle school and early high-school students (TERC, 2012). Both of these curricula have been thoroughly tested for efficacy in teaching course content objectives and have been published for use in schools.

How Is the ASC Curriculum Different From the Astrobiology Curricula Currently Available?

The ASC curriculum is different from both of these existing materials in three major ways. First, these two curricula are available for purchase, while our curriculum guide is available for all teachers without cost, allowing those teachers most in need of quality teaching materials to access ASC without budgetary barriers. Second, our curriculum has been developed with the specific purpose of engaging minority students in scientific thought, helping to decrease the achievement gap between mainstream and nonmainstream students. Last, the ASC curriculum contains information about scientists who serve as role models in minority communities as well as activities that involve the scientists' data. This last difference is crucial, as the availability of role models of similar racial/ethnic and gender background seems to play a key role in students' science achievement and choice of science majors or science-related careers (Lee and Luykx, 2006). Additionally, Blumenfeld and colleagues (1991) describe how incorporating long-term projects into classroom instruction helps to engage students in the solving of “authentic” problems and increases students' investment in classroom learning.

The modules have been designed to be covered in sequence but with built-in flexibility. The lessons can be used as a standalone unit in an after-school program, such as SEMAA, as part of a physical science, biology, chemistry, or astronomy high school course, or spread across a year as application (i.e., laboratory) or enrichment modules (see Supplementary Data online at www.liebertonline.com/ast).

ASC Website and Collaboratory

A website provides access to teachers, developers, and scientists of all materials; evaluation instruments; net-conferencing; and web-based video training materials (VodCasts), datasets, resource materials, and student resources. The website and other Internet tools were used to form a virtual professional learning community based on the work of Schmoker (2006) and Dufour et al. (2006). All of the stakeholders were partners in the revision process through written and oral feedback during the years of the project.

Real Scientific Research Data as Part of the ASC Modules

In their work with the National Science Foundation (NSF)-funded VISIT Teacher Enhancement Project, Hunter and Xie (2001) detailed the barriers for teachers accessing and using the vast amounts of data on the Internet. There are institutional and logistical obstacles, cognitive challenges for students addressing complex, real-world problems, and the often-limited experience of nonexpert teachers in guiding students in using existing scientific research data (Hunter and Xie, 2001). Although teachers are interested in introducing their students to sophisticated concepts and analysis, their training and access to the appropriate computational tools may be beyond their knowledge base and skill set. Research scientists, as experts in their area, have a broader repertoire of techniques in developing and interpreting data sets. The ASC project partnered curriculum developers and teachers with astrobiology researchers to develop data sets that are user-friendly in the high school classroom. Teamwork in this project brought together teachers' eagerness to learn, scientists' know-how, and curriculum developers' ability to organize the data into manageable information matched to appropriate pedagogy. The ASC website provides a place to highlight the careers of contributing scientists. Highlights of astrobiologists showcase women and researchers of color. These profiles were available online for students and teachers to see real astrobiologists “in action” with their research projects.

As an example of how this worked, students learned about Dr. Sue Pfiffner. In her research in astrobiology, she examines extreme organisms and how they exist in environments 2.0 km below land surface inside a goldmine in South Africa. Dr. Pfiffner contributed data collected from water samples in these deep-earth mine fissures. Teachers learned how to assist their students in looking at critical research variables, including sample location; pH; temperature; and concentration of oxygen, sulfate, and nitrates. The students organized and manipulated the data, performed analyses, and interpreted the results. Students had the option to collect water samples near their school and compare that data to the data from the South African mines to better understand how extreme conditions impact organisms. Students discussed how this research on Earth is an analogue to the exploration of Mars as scientists try to discover whether life exists below the surface on that planet. Interesting extensions for students included looking at DNA sequences and membrane lipid profiles.

Capstone Experience: Astrobiology Science Conference

As a capstone experience for the project, teachers participating in the project for at least two of the project-years were invited to attend the Astrobiology Science Conference in April 2010. This conference is an interdisciplinary science conference where planetary geologists, microbiologists, astronomers, educators, and cultural anthropologists gather to discuss and debate the science surrounding astrobiology.

Teachers attended the four-day meeting, with an additional pre-meeting session of the Minority Institution Astrobiology Collaborative (MIAC). Teachers team-taught lessons from the ASC curriculum to the room of scientists, engineers, and informal educators, alternating with technical talks about the science currently underway at various minority-serving institutions.

Between sessions, teachers from these various sites (all serving different populations of students) discussed their teaching experiences with their respective students. These teachers discovered what project staff had been noticing all along—that these diverse students faced many of the same issues, and teachers of these students also faced the same challenges. This experience allowed teachers to experience science research firsthand and learn about the experiences of scientists, engineers, and other teachers while sharing their experiences with others.

Educational Research upon the ASC project

Evaluation of the ASC curriculum includes web-based collaborations among teachers, scientists, and curriculum developers to enhance the modules. Qualitative and quantitative research data were collected and analyzed as part of a three-year pilot study funded by the National Science Foundation. The activities and resulting research investigated a broad spectrum of variables, including change in confidence levels of teachers in the use of research-based instructional strategies, their comfort level in new science content knowledge, and teacher perceptions of change in student academic behavior along with science achievement. In addition to teacher self-report surveys and interviews, the project staff gathered student survey data on science interest and performance scores on end-of-module assessment questions. The intent of evaluating these areas through both teacher and student data is to measure the impact of the ASC curriculum on diverse groups of students by way of a variety of assessment instruments and work samples. The project staff uses this formative evaluation information to revise the ASC curriculum.

Research Questions and Methodology

Did the ASC curriculum support student understanding of core STEM content and basic STEM concepts in formal educational settings (high school classrooms), as well as in informal educational settings after school as measured by educator feedback? Did the ASC curriculum increase science literacy in diverse groups of students as measured by scores on a practice version of the ACT Science Reasoning Test? Did the ASC curriculum provide unique questions that increased student interest and knowledge in STEM areas as measured by student interest and perceived knowledge surveys?

A variety of instruments are used to gather data on the ASC curriculum. Initial findings during year one and two of the grant were designed to determine the success of the ASC materials in meeting the goals of the grant. In year three, staff focused upon educational research regarding the effectiveness of the curriculum with diverse students and teachers. There are two main types of instruments employed: instruments geared toward teachers and instruments geared toward students. Teacher instruments included surveys completed on paper and mailed in, surveys deployed online, teacher lesson-plan feedback, and teacher interviews. Student assessments included surveys of student interest and perceived knowledge about astrobiology topics and a 15-question test taken from the ACT Science Reasoning Test.

The final phase of data gathering and analysis included data obtained from teachers and students at each of four sites. The student data that was gathered consists of student work samples, attitude/interest surveys, and practice questions from the ACT Science Reasoning Test. Data gathered from teachers consist of curriculum maps combining state standards and ASC curriculum activities/assessments, teacher retrospective surveys of confidence and impact, self-report classroom observation forms, and written feedback on individual ASC lessons. These sources of data are combined to produce a final ASC curriculum product suitable for NASA review (in order to become an official NASA curriculum product).

Positive Impacts upon Teachers

Many of the teachers reported that the ASC curriculum field-testing process has had a positive impact upon their teaching, both in pedagogy and in content knowledge. “Mixed-method” professional development sessions in which lessons were taught in the teachers' home classroom with “real students” was reported to be the most impactful part of the professional development during this project. Not only were teachers better prepared to teach the ASC lessons, but they also were “convinced” that the curriculum was appropriate and engaging and produced learning outcomes in their student populations.

One of the major concerns of the project has been the implementation of project activities within the existing school curriculum at each ASC site. To track the implementation of the activities in the context of the professional development modules, we asked teachers to provide their original lesson plans, including ASC lessons at the beginning of the school year. This was compared to actual implementation of the lessons, measured via feedback forms from each instructor. A focus of our professional development program has been implementing the five CREDE standards (Tharp et al., 2003) within science lessons. These standards include joint productive activity by teachers and students producing together, developing language and literacy across the curriculum, connecting school to students' lives, teaching complex thinking, and teaching through instructional conversations. Data collected from teachers and work samples demonstrated that the teachers not only used the ASC lessons in their own classrooms but also incorporated at least two CREDE standards into each lesson.

Positive Impacts upon Students

In-depth data were available from students at four of the eight original sites during year three of the project. A total of 117 high school students who participated in ASC lessons responded to surveys before and after ASC activities. Students were in either the 9^th or 10^th grades (Table 1). These student surveys included questions about student interest in a variety of courses, the number of science courses taken/to be taken in high school, and their perceived knowledge in various areas of STEM-related topics. Questions were asked in which a four-point Likert-type scale was used, with “1” meaning no interest/knowledge and “4” as high interest/knowledge. The second part of the survey included a series of practice questions from the ACT Science Reasoning Test, which was scored for accuracy and reported as a raw number correct out of the total questions asked.

A group of students at two sites were surveyed and matched for both pre- and post-instruction, once in September 2009 and again in May 2010. The survey included questions about student interest in a variety of areas of science and engineering; however, statistically significant differences were only found between the pre-instruction ratings for interest in engineering (M=2.22, SD=0.977) and post-instruction interest in engineering (M=2.39, SD=1.08); t(111)=−1.98, p=0.049). All other areas of interest were not found to be statistically significant (data not shown).

Differences were also found between the pre-instruction and post-instruction groups in the area of perceived knowledge (Table 2). Students reported statistically significant gains between pre-instruction ratings of knowledge in the area of the definition of astrobiology, technology uses in science, importance of astrobiology, and technology uses in astrobiology. Technology uses in astrobiology was a focus of the curriculum, with activities discussing specific NASA missions and spectroscopic methods used to explore the solar system. There were nearly statistically significant results in the areas of careers in astrobiology and ethics of astrobiology (Table 2). Other questions regarding specific areas of astrobiology (geosciences, spectroscopy, comets) were not found to have statistically significant differences when comparing pre- and post-instruction ratings. This is likely due to the implementation of the ASC activities varying, depending upon the individual high school class area—the ASC curriculum was field-tested in biology, chemistry, and physical science classes, and teachers in each course chose the ASC activities that best fit with the standards for that given subject area and grade. Module 1, Introduction to Astrobiology, was the only common activity at all sites and with all teacher lesson plans.

Another section of Module 1 focused on the Nature of Science, including activities such as Tricky Tracks. Students reported significant gains in the areas of knowledge about “what scientists do” and “why scientists ask questions” (Table 3). Interdisciplinary approaches to science such as astrobiology are integral to student understanding of the general topic of the nature of science, as science at the high school level is often compartmentalized to the extent that students view biology, chemistry, and physical science as separate entities rather than sub-disciplines under the grand umbrella of Science.

Analysis by student gender also garnered interesting results, with statistically significant differences in interest in the areas of computer technology, engineering, and writing (Table 3). Male students reported higher levels of interest, on average, than females in the areas of computer technology and engineering, while the opposite was true for writing, with female students reporting much higher interest in this area than males. These gaps in interest (via mean scores) were somewhat narrowed at the end of the school year, although there was still a significant difference between genders in these three areas. Other areas such as physics, space science, mathematics, building models, earth science, and chemistry were not statistically significant between student gender groups.

To address the research question as to how much the ASC curriculum addressed the science literacy of diverse groups of students, a baseline score was established for the students at three of the sites of the ASC project. Students were given a single set of ACT Science Reasoning Test questions containing two or three passages with figures, graphs, and other data, along with five multiple-choice questions asking about the information requested (a total of approximately 15 questions per administration). This instrument, combined with the interest and perceived knowledge surveys administered, provides a good measure of potential changes in student science literacy as measured by changes in ability to reason scientifically and interpret given data. It is also beneficial for the student to gain exposure to the types of questions asked on the ACT test, as most of the students of teachers participating in the project are in 9th and 10th grade and are soon preparing for college entrance exams. Tests of content knowledge were considered secondary to tests of science literacy, student interest, and student perceived knowledge because of research implicating the importance of the latter three factors in students of color and their school science experience (Lee and Luykx, 2006).

Students who answered the ACT questions on the pre-instruction survey and post-instruction survey showed significant differences between these scores (Table 4). The students were given a variety of question topics, not just astrobiology-related topics, and given different questions pre-instruction and post-instruction. Students were given a total of 15 multiple choice questions as a pre-test and a different set of 15 multiple choice questions from ACT practice tests as a post-test. This statistically significant increase shows that the project has had a positive impact upon diverse students' level of science literacy. There were no significant differences between male and female groups on the ACT questions (data not shown). These two are critical findings of the educational research portion of the project, as ongoing science literacy and scientific reasoning are vital to the diverse public's understanding of science as well as skills all students should be expected to have upon entering postsecondary study.

Discussion

The ASC curriculum was designed with several features in mind, focusing on diverse students and teachers, increasing the ability of teachers to bring cutting-edge science knowledge into the classroom, increasing students' knowledge about astrobiology, and increasing students' ability to reason scientifically. Data gathered during the project showed statistically significant gains in students' perceived knowledge about astrobiology in general, including careers, ethics, technology, and the importance of astrobiology. Students also showed significant gains in the ability to reason scientifically, as measured by the ACT Science Reasoning Test. The integration of science topics inherent in the study of astrobiology is important for high school students to understand, increasing students' understanding of the whole of science rather than the individual parts of biology, physics, and chemistry. Further educational research into the impact of astrobiology upon students' science reasoning, argumentation, and nature of science process skills is important to best understand the benefits of teaching astrobiology in the secondary classroom.

Future Work

Electronic copies of the ASC curriculum are available free of charge via email correspondence with the author, and we are currently preparing articles for practitioner-oriented education journals based upon the unique activities of the ASC curriculum. Further activities in this area have involved continuing work in mentoring high school students through outreach initiatives such as S.A.G.A.N. and university initiatives contained within undergraduate programs focusing upon students researching astrobiology-related areas of study. Additionally, lines of research investigating cultural differences in student views of the nature and process of science are underway, addressing issues of underrepresentation in science careers through expanding the research literature on diverse P-16 student views of the Nature of Science.