3.Pulse Monitoring with RGB LED and Microcontroller

In this lesson, students will explore the relationship between heart rate, physical activity, and emotions using a pulse sensor and an RGB LED. By integrating biology, physics, and programming, students will measure their pulse, analyze how physical exertion or stress affects heart rate, and modify a microcontroller-based system to display real-time feedback.

Through hands-on coding, students will customize the LED colors to represent different pulse rates and add personalized messages in Armenian when no pulse is detected. The activity encourages interdisciplinary collaboration, as it involves elements of science, computer programming, and physical education.

The lesson fosters critical thinking, problem-solving, and data interpretation, making learning both interactive and applicable to real-life health monitoring.

Learning Objectives

Understand the physiological function of the heart and how heart rate is affected by physical activity, emotions, and environmental factors. Measure and analyze heart rate using a pulse sensor and interpret real-time data. Communicate findings effectively through discussions, data interpretation, and reflections on how heart rate changes in response to various stimuli. Collaborate across disciplines by integrating science (biology & physics), computer programming, and physical education into a single project.

Reflection

This lesson was an exciting and interactive way to combine biology, physics, and programming. Students were fascinated by how they could measure their heart rate using a pulse sensor and visualize the data with an RGB LED. They actively participated in testing their pulse before and after physical activity and were eager to see how their heart rate changed.

Challanges

Some students struggled to get a stable pulse reading. To address this, I guided them on proper finger placement and sensor sensitivity.

A few found the coding part complex at first, especially understanding how the RGB LED changed color based on heart rate. However, as they experimented with the code, they gained confidence.

Since we couldn’t test the entire class, I worked with a small group and shared their results with others. Next time, I would plan for a larger-scale experiment.

Creativity Students successfully modified the Arduino code, adding an Armenian message: “Որտեղ է քո մատը?” (Where is your finger?) when no pulse was detected.

Some wanted to add a buzzer to alert when pulse rates were too high or low. Collaborating helped students connect heart rate with physical activity and emotions.

The lesson showed how technology can be used in health monitoring, making it a real-world, interdisciplinary experience.

The project inspired discussions about wearable tech, fitness trackers, and medical devices.

small video aboud pulse monitoring Link name

[https://youtube.com/shorts/qQ6AELY-0kY?feature=share]

Connecting the Pulse Sensor and RGB LED to Arduino This step introduces students to the basics of pulse measurement and visual feedback using an Arduino, a pulse sensor, and an RGB LED. They will learn how the heart rate changes due to different physical activities and emotions. The RGB LED will visually represent heart rate variations, with colors changing based on pulse levels. Connect the Pulse Sensor to Arduino:

VCC → Connect to 5V GND → Connect to GND Signal (S) → Connect to A0 Connect the RGB LED:

Identify the Red, Green, and Blue (R, G, B) pins. Use 220Ω resistors for each color pin. Upload and Test the Code:

Open Arduino IDE. Upload the pulse detection code. Observe how the LED changes color based on pulse rate: If the pulse is more than 65- blue

if the pulse is less than then65- green

Experiment and Modify the Code:

Encourage students to modify the code to display messages like “Where is your finger?” when the sensor is not detecting a pulse. Test how exercise, excitement, or relaxation affects their pulse rate. I implemented this lesson over 2 class periods, but I wrote the lesson plan for one class period.

You can find Lesson plan on ScopesDf

Reflections

1. Collaboration During this Field Activity, collaboration played a crucial role in shaping both the technical setup and the instructional approach. I consulted with Fab Academy (FLA) participants during the planning phase to discuss which sensors and outputs would be most engaging and effective for students.Also I colaborate with our Biology teacher, to know more about blood ansd circulation in our body.

2. Instructional Challenges One of the main challenges I encountered was getting a stable and accurate pulse reading from the sensor. Some students struggled with sensor placement or were not patient enough to hold their fingers steady. I addressed this by guiding them step-by-step and explaining how minor adjustments can improve the reading. I also emphasized teamwork, allowing students to help each other with placement and reading interpretation.

Another challenge was coding complexity. For students with less experience, understanding how RGB color changes based on pulse rate was initially confusing. I scaffolded the lesson by breaking down the code and letting them change small parts first (just one LED color and the sentence which they want to see). This helped build confidence before moving to more complex tasks.

1. Integrating Disciplines I would classify this lesson as interdisciplinary because it meaningfully connects biology (heart rate), physics (LED operation, circuits), computer science (coding), and physical education (movement and pulse changes). The disciplines are integrated in a cohesive way where students apply knowledge across fields to build a working prototype.

To move toward a transdisciplinary level, I would add a real-world problem for students to solve—such as designing a prototype for elderly people or athletes—and involve them in user research or empathy interviews. This would further deepen the relevance and require them to move beyond academic knowledge into applied, socially driven innovation.

1. AI Usage I use AI , to know were can i find some codes.

2. Reflection on the Course This course has significantly transformed my approach to teaching. I’ve moved from teacher-centered instruction toward learner-centered, hands-on exploration. I now focus more on integrating disciplines, encouraging collaboration, and using technology not just as a tool but as a medium for creative expression and problem-solving. I would like to explore more about wearable technology, machine learning for beginners, and data visualization in student-led projects.

To support other teachers, I plan to lead workshops where I share lesson templates, project samples, and encourage co-creation of ideas. I also aim to help them integrate digital fabrication tools like 3D printers, laser cutters, and Arduino into their subject areas in practical and manageable ways. By showing small steps and easy entry points, I hope to make the digital world less intimidating and more inviting for educators.

Formal curriculum Alignment Armenian standart

The internal environment of the organism. Cardiovascular system TOPIC GOAL point2-Develop ideas about the interconnected activities of the cardiovascular system and other systems.

Blood Pressure and Pulse. Understand the difference between hypertension and hypotension, explain the pulse. Understands the difference between hypertension and hypotension, explains the pulse.

This activity aligns with the Natural Science curriculum in Armenia for Grades 7–9, where students: Study the human circulatory system and understand the heart’s function. Learn to interpret physiological responses to exercise and emotion. Use sensors, simple circuits and programming. Practice scientific investigation and technology-based experimentation.

MAX30102 Heart Rate Sensor with Arduino

Competence	Description	Basic	Proficient	Advanced
Scientific Understanding of Heart Rate	Shows minimal understanding of how heart rate relates to physical activity or emotion	Describes heart rate changes with basic understanding, but lacks clarity or depth	Accurately explains how physical or emotional states affect pulse rate	Demonstrates deep understanding by drawing connections between heart rate, emotions, and real-world health applications
Programming & Technical Application	Uses the provided code with little or no modification.	Makes small modifications to the code but struggles with logic or function.	Customizes code to match pulse levels to RGB colors and adds simple messages	Thoughtfully extends code with additional features (e.g., buzzer alerts or personalized messages) and ensures functionality.
Use of Sensor and Electronic Components	Struggles to set up sensor or connections correctly.	Connects components with guidance and tests functionality with limited success.	Sets up and tests components independently, with functioning pulse feedback.	Demonstrates mastery by troubleshooting and optimizing the system for reliable readings.
Creativity & Personalization	Little to no personalization in the code or output.	Adds basic customization (e.g., one LED color change or short message)	Meaningfully personalizes outputs to represent health states or messages (“Where is your finger?”)	Creatively integrates multiple elements (messages, audio alerts, visual effects) to enhance communication and user experience.
Collaboration & Discussion	Rarely interacts with peers or reflects on the activity.	Occasionally shares observations or listens to others.	Actively participates in group discussion and idea sharing.	Leads or inspires collaborative exploration and reflects deeply on the interdisciplinary impact