A Web-based instructional module for teaching middle school students engineering design with simple machines

Journal of Engineering Education, Oct 1998 by McKenna, Ann, Agogino, Alice

ABSTRACT

The current work describes an instructional module that emphasizes integrative design using six simple machines: the lever, the wheel and axle, the pulley, the inclined plane, the screw, and the gear. The emphasis ofthis module is to have students investigate the underlying scientific and mathematical properties of the "machines," and then integrate this knowledge to design creative solutions to problems. This simple machines module makes use of an original web-based multimedia learning environment as well as off-line, hands-on building activities with the LEGOTM Technic I set. The current instructional module was used in a pilot study in an Introduction to Engineering class, and we include preliminary results from this study.

I. INTRODUCTION

The current paper provides an overview of an instructional module that was developed for middle school students. The module is intended to introduce students to the practice of engineering and, specifically, to have the students design and learn with simple machines. A web-based design was chosen in order to make the module widely accessible, as well as to make use of the Internet and advancing multimedia capabilities. The recent interest in connecting schools to the Internet has created a need for the development of effective and easy to use Internet-based instructional materials.

In addition, interest in pre-engineering curricula has become more widespread as evidenced by the number of recent publications involving engineering curricula for K-12.1-3 The present work contributes to this expanding research community, but it also offers a unique perspective through its use of an interactive web-based instructional environment.4 Features of the environment are programmed in Java5 which allows for interactive computer simulations via the Internet. The module also includes hands-on building activities with LEGOS"M The on-line computer simulations, combined with the hands-on design and building activities, encourage the students to make connections between the more abstract principles and the actual physical system. This is a necessary connection that is often overlooked in engineering education.

This paper describes the cognitive goals and the design considerations that were outlined for the instructional module. The cognitive goals define the learning that should take place among the students. Since the current module is web-based, it is also necessary to discuss the design guidelines that were followed in the development of the user-interface. For example, some of the design guidelines were to make the module interactive and gender equitable. The current paper illustrates and describes specific features of the user interface that were employed to reflect these guidelines. Finally, the current instructional module was used in a pilot study in an Introduction to Engineering class for middle and high school students. Student feedback and results from this study are also presented.

II. THE ENGINEERING DESIGN PROCESS DEFINED FORA K-12 CURRICULUM

In order to provide a framework for a pre-engineering curriculum, it is useful to discuss engineering design and its associated abilities and processes. The field of engineering is quite broad and the types of activities that individual engineers engage in can be quite diverse. Consequently, the framework that is discussed here is not meant to be inclusive, or necessarily descriptive, of every engineering profession or job function. The present description of the engineering design process is intended to serve as a guideline for the development of the current pre-engineering instructional module.

The basic framework for the engineering design process is shown in figure 1. This figure illustrates a set of steps, or cognitive processes, that engineers generally complete while developing solutions to engineering design problems. The first step the engineer must perform is to define the problem that needs to be solved. It is important to identify the exact needs for a particular problem so that the solution matches the needs of the customer or end-user. The design issues are not always obvious so careful attention is needed in defining the scope and parameters for each project.

After defining the problem the engineer moves into the stage of developing a solution. This solution-finding or design stage can consist of numerous activities and associated skills which we summarize into three broad categories: research, simulate, and prototype. These three activities represent an iterative process that the engineer cycles through repeatedly to develop a solution. Research involves investigating existing work and understanding the governing principles that apply to the particular problem. For example, if the project is to design a new commercial aircraft, it would be useful to understand how existing aircraft are designed, and it would be essential to understand the laws of motion for flight.

Another step in the iterative process is to conduct simulations of possible solutions. The simulations are based on the underlying principles, such as the laws of motion for flight, and are a way to test and examine the engineer's predictions and hypotheses. The third category in the solution-finding process is prototyping. A prototype, or a physical working model (full size or scale), is often built to investigate the actual functioning of the proposed idea. Prototyping tests the functionality of the simulated design and allows investigation of manufacturing issues. Ultimately the design idea is informed by the results obtained from the processes of researching, simulating, and prototyping. Therefore, the design develops as the engineer cycles through these processes and synthesizes the information.