William H. Leonard

Performance Assessment of a Standards-Based High School Biology Curriculum

JN response to what was widely perceived as inadequate teaching of precollege science in the United States, the National Science Foundation supported the development of the Benchmarks for Science Literacy (AAAS 1993) and the National Science Education Standards (NRC 1996). One of the specific problems addressed by these national standards efforts was that secondary science historically has been taught primarily through lecture with emphasis on long lists of trivial facts and vocabulary words, which often are to be memorized (Bowyer 1990; Brandwein 1981; Champagne & Hornig 1987). This practice has been widely supported by traditional, encyclopedic science textbooks which continually grow in size as more information is added to each new edition. Both AAAS and the NRC attempted to aid science curriculum developers in content selection by identifying a small subset of the most important science concepts rather than a long set of facts that attempt to cover an entire subject, as is the case for many traditional science curricula. Also, unlike the dominant traditional curricula, AAAS and NRC strongly recommend that science curricula devote significantly more time to developing scientific thinking skills and understanding the nature of science. Both organizations promote student learning through engaged investigation as opposed to passive listening and speak also to the desirable role of the teacher as being distinctly student-centered and inquiryoriented. Science curricula recently funded by the National Science Foundation have aligned themselves with the Standards and Benchmarks by reducing numbers of concepts and topics and de-emphasizing less central concepts and topics in favor of additional activities that require student thinking, decision-making, inquiry, collaboration and communication. Observers of students using these new curricula have noted that they are engaged extensively in serious discussion and scientific inquiry. Since the national standards and corresponding curricula developed to meet the standards are quite recent, there is yet little research literature on the effectiveness of these curricula. ChemCom (Sutman & Bruce 1992, 1993; ACS 1998), a high school chemistry curriculum developed with funding from the National Science Foundation and the American Chemistry Society predated the National Science Education Standards. Developers of ChemCom say that it matches the standards, especially in its 1993 and 1998 editions. One study of ChemCom at the University of Texas (Mason 1998) compared student achievement in college general chemistry by students who had either a traditional high school chemistry curriculum or the 1988 or 1993 editions of ChemCom. After eliminating variables such as having taken AP Chemistry or a second year of advanced chemistry in high school, there were no statistically significant differences in performance between students who had one year of ChemCom versus those who had one year of a traditional chemistry course in high school. Biology: A Community Context (Leonard & Penick 1998a) is an introductory high school biology curriculum developed in response to the national standards and needs. Funded by a

What's Important in Selecting a Biology Textbook?

2.3 million National Science Foundation grant to Clemson University, the project goal was a teacher-developed curriculum that would be standards-based, activity-oriented, inquiry-centered and overtly constructivist. As part of the evaluation component, we were interested in knowing if this standards-based curriculum would produce any greater learning of selected science concepts identified in the Standards and Benchmarks and any greater understanding of scientific inquiry skills than did the traditional curricula that dominate schools today. BACC was designed to encourage broad goals (Penick & Bonnstetter 1993) by following a research-based instructional strategy (Leonard & Penick 1998b; Penick 1999).

Designing an Extended Discretion Laboratory Investigation

Selecting a biology textbook can be a very interesting process. This is especially true for the introductory high school biology course where the arena is large and public, open to a myriad of interests which are economic, pedagogical, scientific, political and even religious. How does one possibly enter this process objectively? This article provides a framework for more objectively selecting a biology text based upon credible recommendations from the professional literature. This framework will especially draw from recent research findings in science, learning theory and instruction. Actually, today we do not select only a textbook. Over the past decade the market has moved from textbooks only, in nearly all subject areas, to comprehensive curriculum packages. Packages available in biology typically include, in addition to a student text, an annotated teacher edition of the text, computer test banks, a variety of optional student activities and student study guides. The packages also frequently contain teacher resource books with a wealth of information for ordering and maintaining materials, safety notes, general pedagogy, blow-byblow instructional tips, lists of media and printed resources, and options for use of state-of-the-art high-technology devices such as computer lessons, computer interfacing and interactive videodisc. The biology teacher probably has a greater wealth of instructional strategies from which to draw than does any other educator. All of these components need to be considered in the selection process. The result is that selecting appropriate course materials can be confusing and time consuming, especially if one looks beyond the pretty pictures and topic coverage in a biology text. Where, then, does one begin?

Biology Education with Interactive Videodiscs (II): Development of Laboratory Simulations

WOULD YOU LIKE TO create your own biology laboratory activities that require the students to think out part of the procedure themselves through the exercise of discretion? Are you interested in training your students to deal with uncertainty in the laboratory yet still develop basic biological concepts? The Extended Discretion (ED) laboratory approach was described in a recent article (Leonard 1980). The article explained the development of the ED approach as a result of research at the Lawrence Hall of Science, University of California at Berkeley. The original article also presents a description of the concept of extended discretion laboratory learning, relationship to learning theory in science education, and a study where the method was shown to be productive for high school biology students. This article outlines a step-by-step procedure for the biology teacher to design and conduct an extended discretion laboratory activity and it gives a detailed example, lists expected teacher and student behaviors, and discusses the control of student discretion over the school year. The basic idea behind the ED approach is that students are required to exercise discretion in the use of available resources during the laboratory activity instead of merely following a recipe-like procedure. Because the approach fosters student independence, it has some similarities to biology teaching strategies previously characterized as deductive (Curtis 1950), enquiry (Schwab 1954), discovery (Bruner 1969), and nondirective (Egleston 1973). The ED approach is different from these other approaches in that there are only specified times at which a student can receive teacher assistance (review points), and there is a systematic attempt to control and account for the period of time a student is required to work with-

A BSCS-Style Laboratory Approach for University General Biology

William H. Leonard William H. Leonard is an associate professor at Louisiana State University, t Baton Rouge, LA 70803, where he is appointed jointly in the Department of Zoology and Physiology and in the Department of Curriculum and InstrucA tion. He earned his B.A. and M.A. in biology at San Jose State University and his Ph.D. in biology education at the University of California at Berkeley. Leonard has been a frequent contributor to ABT and to other science teaching journals. He is an active researcher in the areas of laboratory teaching, interactive videodisc instruction, and textbook questioning strategies. This article was based upon his work while on the biological sciences faculty at the University of Nebraska-Lincoln, where he was the recipient of the Amoco Distinguished Teaching Award in 1983.

BioCom? Is That like ChemCom?

The author is associate professor of Life Sciences and Instructional Coordinator, School of Life Sciences, University of Nebraska-Lincoln 68588. He holds a B.A. in biology and an M.A. in biology education from San Jose State University, as well as a Ph.D. in science education from the University of California at Berkeley. He has taught science and biology at both the secondary and university levels, and is a member and fellow of the graduate faculty at the University of Nebraska-Lincoln. Dr. Leonard is a member of the Beta Beta Beta Biological Honor Society and holds memberships in several other professional organizations, including AAAS, NABT, NSTA, and Phi Deltan Kappa.! He isthe aut+hor or coautfho%r of mainy articles and iinstutoa _ulctos nldn Lbrtr netgtosi ilg

Interfacing in the Biology Laboratory: State of the Art

B ioCom (actually Biology and the Community), an introductory biology curriculum for the heterogeneously mixed high school classroom of the year 2000 and beyond, is currently being developed under a grant from the National Science Foundation. Philosophically it is similar to ChemCom (American Chemical Society 1988 & 1992) in providing activities with deliberate connections to the students community. But there are also some important differences. The purpose of this article is to share the philosophy, development, content structure, and general instructional strategy of this emerging curriculum which is very different (perhaps radically different) from current biology curricula. BioCom will address recent recommendations by national commissions and science education research, and also reflects the grave concern over the way high school biology is currently taught (AAAS 1989; National Research Council 1990). We will discuss similarities and differences between BioCom and ChemCom, and will take a look at what a BioCom classroom might look like.

The Question Is Where Should the Questions Be? Does Their Placement in the Text Make a Difference in Learning?

It is commonplace now to see microcomputers used in the science classroom, especially for drill and practice, review, testing and other tutorial functions. For several years microcomputers have been used for data analysis and computations such as statistical analysis. Just a few years ago, a new dimension was added by interfacing the microcomputer to the videodisc player. Several applications and programs using the interactive videodisc have been described in this column and elsewhere (Leonard 1983, 1985). The main advantages of this new videodisc technology are broadcast-quality video images, greater speed in assessing video materials and more extensive interactivity for the user. The interfacing of laboratory instruments to the computer has been done in industry and scientific research almost as long as the computer has existed. This application has been the source of many ideas for current classroom use of interfacing. Only in the past two or three years has interfacing been used with success in the science classroom, primarily because of increased activity in classroom use of the microcomputer. This article will focus on some of the very basics of interfacing, what is now state of the art and the educational benefits of computers interfaced to laboratory instruments for use in biology classrooms. The simplest possible interface consists of a switch connected by two wires to a port in the microcomputer. The computer can detect if the switch is on or off approximately 80,000 times a second. The switch can be replaced by a photodetector and interruptions in the beam can be timed over very short or long periods of time. Instruments that have a signal output, such as pH meters, spectrophotometers and chromatographs, can be connected directly to the computer. If measurement of continuous variables such as temperature or light intensity is desired, an analog to digital converter (ADC) is added. ADCs are basically transducers which convert the input variable into a voltage or resistance. A thermister can measure temperature and a phototransistor can measure light intensity. Transducers can also be used to measure humidity, radioactivity, pressure and the presence of various gases (Nicklin 1985). Most of these take advantage of the built-in game controller or paddle port found in most microcomputers. Typical paddle ports can read a variable resistance in the range of 0-500 kiloohms. There are many other possibilities.

A Conceptual Model for the Study of Biomes

William H. Leonard William H. Leonard is an associate professor at Louisiana State Univ., Baton Rouge, LA 70803, where he is appointed jointly in the Dept. of Zoology and Physiology and in the Dept. of Curriculum and Instruction. He earned his B.A. and M.A. in Biology at San Jose State Univ. and his Ph.D. in Biology Education at the Univ. of California at Berkeley. He was a high school biology teacher in San Jose, California for 13 years and a member of the biological sciences faculty at the Univ. of Nebraska, where he received the Amoco Distinguished Teaching Award in 1982. Leonard has published more than 40 articles in science teaching journals, including ABT, Science Education, Journal of Research in Science Teaching, Journal of College Science Teaching and The Science Teacher. He authored a biology laboratory textbook, published by Burgess, Co. An active member of NABT, Leonard is coordinator of Region VI and chair of the Scientific Integrity Committee.

This Month's Feature Article & a New ABT Department

William H. Leonard William H. Leonard is an associate professor at Louisiana State University, Baton Rouge, LA 70803, where he is appointed jointly in the Department of Zoology and Physiology and in the Department of Curriculum and Instruction. He earned his B.A. and M.A. in biology at San Jose State University and his Ph.D. in biology education at the University of California at Berkeley. Leonard has been a frequent contributor to ABT and to other science teaching joumals. He is an active researcher in the areas of laboratory teaching, interactive videodisc instruction, and textbook questioning strategies.