The impact of STEM curriculum on students’ engineering design abilities and attitudes toward STEM

Abstract

While it has been recognized that science, technology, engineering, and mathematics (STEM) education requires an interdisciplinary approach, integrating multiple subjects in a meaningful way remains challenging for teachers. This study aimed to design a STEM curriculum, emphasizing explicit and continuous scaffolding of students’ reflection on scientific and engineering knowledge. The primary goal was to foster knowledge integration in their engineering designs and enhance their attitudes toward STEM. The study involved fifty tenth-grade students who were guided to discuss and reflect on relevant scientific and engineering knowledge and to apply mathematics for data collection and analysis during the design of their technology products. The research instruments included an assessment of the progression of knowledge integration in students’ engineering designs through student journals and pre- and post-test surveys on attitudes toward science, technology, engineering, and the learning environment. The results reveal that the introduction and explicit scaffolding students’ reflection on scientific and engineering knowledge led to a gradual improvement in knowledge integration within their engineering designs. Students also significantly enhanced their attitudes toward STEM and the learning environment compared to the general school curriculum. This study contributes to interdisciplinary learning that promotes the integration of scientific and engineering knowledge in students' engineering design processes, and to interdisciplinary assessment that evaluates students' knowledge integration across learning progressions and outcomes.

Appendix 1

Teaching activities based on 6E

The seven teaching activities and corresponding 6E teaching model progressed follows:

Activity 1: Brainstorming about flat speaker structure

The first activity is the Engage stage in the 6E framework, which aims to enable students to connect their own experiences to the learning content to stimulate learning interest. At the beginning of the course, the teacher presented a stereo speaker that the students were familiar with and then played an exhibition video of new technologies created using flat speakers to arouse the students’ curiosity and attention. Next, the instructor asked students questions to contrast traditional stereo speakers with this flat speaker technology. Finally, the instructor asked students to think about the physics concepts and rationale used in flat speaker design and to draw structure diagrams of flat speakers that they believe could produce the maximum volume.

Activity 2: Disassembling a real stereo speaker

The second activity is the Explore stage in the 6E framework, which seeks to provide opportunities for students to develop their own experiences and understanding of the topic. In this study, actual stereo speakers were provided so that students could observe and examine the internal structure. Students were guided to observe the key components and functions inside the speaker, such as the winding of the coil, the position of the magnet (as tested by a paper clip), and the vibration of the coil inside the ring magnet after it is connected to a sound source. Finally, they were asked to revisit the concepts involved in the structure diagrams created in Activity 1 and to redraw the structure of a flat speaker that could produce the maximum volume.

Activity 3: Explaining the magnetic effect of an electric current

The third activity is the Explain stage of the 6E framework, whose primary goal to guide students to rethink what they have learned by explaining the related concepts in the current context. The way in which sound is transferred through the speaker wire was discussed and explained by both students and instructors: sound is generated by the rapid vibration of an object and transmitted to the human ear through the medium and then converted into an electric current in the wire; this is like connecting a sound source cable to a phone to send sound waves to a speaker or amplifier in the form of electric current.

Next, the instructor introduced the concept of the magnetic effect of an electric current, which is the focus of the scientific models in this curriculum. The instructor first introduced the fact that a current-carrying wire produces a magnetic field using a solenoid as an example to demonstrate Ampère’s right-hand grip rule of determining the direction of a current and a magnetic field. Then the instructor proposed the following situation for students to consider and discuss: if a non-movable magnet is installed on the side of the current-carrying solenoid, what would happen between the solenoid and the magnet if the value and direction of the current inside the solenoid are changed? Students discussed and concluded that when the solenoid in the speaker is connected to an alternating current, the magnetic field changes constantly. There is both attraction and repulsion between the solenoid and the magnet, which vibrates the diaphragm connected to the solenoid, thus generating sound.

Although the underlying principle of sound generation in both flat speakers and traditional speakers shares similarities, students were encouraged to use the interaction between the solenoid and the magnets in 3 dimensions in stereo speakers and to think about the interaction between their flat conductive wire pattern and the magnets in 2 dimension in flat speakers. Hence, after explaining and discussing the scientific model of sound and electromagnetic force as it applies to stereo speakers, students were encouraged to rethink whether the designs of the flat speakers they had produced in Activity 2 were reasonable in light of this scientific model. They were also expected to revise their flat speaker structure diagrams and reconsider their underlying scientific principles.

Activity 4: Making a flat speaker

The fourth activity comprises the Engineer and Evaluate stages of the 6E framework. The purpose of the Engineer stage is to enable students to apply their understanding of scientific models to their engineering designs and consider whether their models would operate successfully. The purpose of the Evaluate stage is to enable students to assess whether their products function in line with their expectations and consider how to modify them.

First, the instructor provided a brief introduction to the experimental materials and the use of decibel meters and amplifiers. Then students shared the advantages and disadvantages of the individual structure diagrams from in Activity 3 within groups and designed one group structure diagram in detail, which was then engineered and tested. The teacher encouraged the students to analyze the factors that impacted the volume of their flat speakers, modify their products, and record their improvements based on their scientific knowledge of electromagnetic force and their engineering knowledge about the essential components of the stereo speaker. In the process of making and testing the flat speakers, students might encounter many difficulties and failures, including sticking wires, absence of sound, and low prototype volume. Finally, each group demonstrated their design, creation, and revision process to the entire class.

Examples of flat speakers that students tested are shown in Fig. 2. In order to make flat speaker, these students stick the copper tape in a flat spiral shape. They tested various kinds of shapes and consider whether these different shapes of copper tape could produce enough strength of magnetic field based on their scientific models of electromagnetic force.

The following steps (Activities 5 and 6) repeated the Explain, Engineer, and Evaluate stages of the 6E teaching model. The purpose of these activities is to encourage students to explore the relationship between the volume and the structure of flat speakers more in-depth through reflection on scientific and engineering knowledge after engineering flat speakers in Activity 4.

Activity 5: Explaining the factors that affect speaker volume

The fifth activity is the Explain stage of the 6E framework. After students gain an understanding of the basic scientific and engineering knowledge of flat speakers in Activities 3 and 4, the instructor leaded students to consider the factors that influence speaker volume according to what they have learned from the scientific model of electromagnetic force. In this activity, students predicted the factors affecting the strength of an electromagnet as well as the interaction between the electromagnet and the magnet in a speaker.

To encourage students to use the scientific model of electromagnetic force in enhancing their products, the instructor first proposed the following question: How can the magnetic field of a long, straight, current-carrying wire be amplified? After group discussion, the instructor prompted students to summarize three main methods: (1) increasing the current in the long, straight, current-carrying wire; (2) tying together several long, straight, current-carrying wires; (3) bending the long, straight, current-carrying wire into a circle.

Then the instructor asked the following: If there is only one current-carrying coil placed with a magnet in the center of the speaker, but the sound is too low after the experiment, how can it be improved? Through group discussion and presentations, students were encouraged to contemplate the relationship between volume and the magnetic force between coils and magnets. Finally, the instructor helped students to postulate which factors that might influence the volume, such as radius of the current-carrying coil, the number of coils, the amount of current flowing, or the strength of magnets.

Activity 6: Discussing and testing the factors affecting speaker volume through experimentation

The sixth activity comprises the Engineer and Evaluate stages of the 6E framework. First, students were asked to analyze the flat speaker designed in Activity 3 and discuss how they might increase the volume of the flat speaker significantly if they could only change one variable according to the scientific model of electromagnetic force. Then they were instructed to design and conduct an experiment to examine whether the factor they had proposed would influence the volume of their flat speaker by inspecting data concerning the relationship between the changed variable and the volume of the flat speaker. Finally, each group presented and explained their findings to the entire class and examined whether their findings were consistent with their predictions according to the scientific model of electromagnetic force.

Activity 7: Designing a holiday card with flat speakers with maximum sound volume

Activity 7 comprises the Enrich and Evaluate stages of the 6E framework, which enable students to apply what they have learned to new contexts and assess whether they have applied the principles they have learned in class to design their products. The instructor asked students to design holiday cards for students to apply what they have learned to new applications and utilize their artistic creativity. Then students were asked to examine their own designs according to what they have learned about scientific models and engineering knowledge to produce the maximum volume. An example of a holiday card that was tested is presented in Fig. 3. In the following example, students place several magnets in the center of a spiral-shaped Christmas tree with conductive wires.