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

Finally, issues may arise during the solution process that may cause the engineer to re-evaluate the originally defined problem. It may be necessary to step out and evaluate the progress, possibly redefine the problem, relax some of the constraints, or simply abort the mission. This is illustrated in figure 1 by a dashed line. These activities, skills, and processes serve as an outline for a pre-engineering curriculum which is intended to familiarize students with the engineering profession and to enable students to engage in and develop these skills.

III. COGNITIVE GOALS

The overall objectives of this module were to help students develop an understanding of, and spark an interest in, how simple machines work, and to familiarize students with the practice of engineering. Based on these objectives the cognitive goals for the module were established.

The learning goals of the module are to assist students:

in developing concepts about simple machines

in developing and practicing engineering problem solving skills. These skills entail using their concepts about mechanical devices to produce creative solutions to problems. Activities basically coincide with the iterative engineering design process of research,simulate-prototype

in making connections between the physical devices, the mathematics, and the scientific principles

by encouraging self-reflection on their work, the activities, and hence their learning.

The first cognitive goal will be addressed throughout all the activities in the module. During these activities the students will be working and designing with simple machines and all of these activities will contribute to their concept development. In this case, "concept development" includes learning about the names and functions of each of the devices and their parts, and recognizing common uses for each of the simple machines. In addition, students should begin to recognize that simple machines are part of many common devices and this commonality increases the relevance of the learning.7,8

Middle school students are likely to have experience with the "simple machines" that are ubiquitous in everyday life. Common everyday devices based on the fundamental principles of the six simple machines include a wheelbarrow, bicycle, sliding board, car, etc. Students should have experience with all of these devices, at least to the extent of having seen or used them at least once. Therefore, this experiential knowledge is a base on which the students can build a more comprehensive and robust understanding of simple machines. This module builds on the students' existing experiential knowledge in order to expand it to include the underlying principles behind these everyday objects. This "principle" knowledge can then be used to design creative solutions to novel problems.

The second cognitive goal involves engaging the student in the "engineering process." The students will be solving design problems throughout the instructional module. The module is organized so that the students work through a set of activities for each of the simple machines. One of these activities is to use a particular machine to solve a given design problem. As the students work through the set of activities for each simple machine, they will also be working on a final project that makes use of two or more machines. Therefore the students will have multiple opportunities to solve design problems and engage in the engineering process.