Cross-Curricular Connections: Exploring Our "Holiday Celebration" Unit

This month’s unit feature focuses on our Holiday Celebration project in Content Library Junior, our subscription content aimed at younger and less experienced learners. Students work in Tinkercad, an online app used to teach electronics, 3d modeling and design, and coding. Content Library Junior explores each of these areas in Tinkercad throughout different modules. Holiday Celebration focuses on coding and basic electronics concepts to create a circuit that plays the melody of “Let It Snow.” As we enter into the holiday season, this is a festive module that provides an intriguing challenge for those students with an interest in engineering!

Ohm’s Law

Ohm’s Law is a mathematical relationship among the current, voltage, and resistance of an electrical circuit.  It is expressed as an equation as V = I x R where V is the voltage, I is the current (from the German intensität), and R is the resistance. This relationship was discovered by the German scientist Georg Simon Ohm. Ohm's Law helps us to understand why we need a resistor with a resistance of around 220 Ohms (Ω) to prevent the current from overloading an LED. 

Engineering projects in Content Library, the part of our content targeting older students, utilize Ohm’s Law and explore the concept to a greater degree. At the elementary level, we do not expect students to have an in-depth understanding of this principle. Rather, we introduce it to provide context for why we adjust the resistance level of the resistors, as well as to lay the groundwork for more extensive engineering challenges further down the road. 

Introducing this concept at a basic level increases the likelihood that as students’ skills develop and progress, when working with Ohm’s Law again in further projects, they may more easily connect the dots regarding how to use this concept in their circuits.  They will already have a very basic understanding of what it does! In the Holiday Celebration project, students take a lesson that requires them to solve very basic problems using Ohm’s Law to build familiarity.

Creating the Circuit

In the engineering modules in Content Library Junior, we teach students how to create circuits operated both with and without code. Some circuits are created and powered by a simple battery. In others, an Arduino, a small microcontroller that reads inputs (like various kinds of sensors) and controls outputs (like LEDs), acts as the battery. This means that students also have to learn how to write code to operate the microcontroller. Holiday Celebration is a project that incorporates an Arduino and provides the additional challenge of writing code.

A great thing about Tinkercad is that students do not need an actual Arduino (or any of the other electronic components) to build a circuit!  Instead, everything is done with virtual and simulated components in a browser-based application.  This helps younger students become familiar with the components and how to use to a breadboard to assemble their circuits before they have to worry about losing or damaging physical parts.

To start with this project, students first learn how to identify the hardware required for the circuit, as well as how to connect the circuit properly. Students learn that a closed circuit allows electricity to flow without interruption. The hardware needed for this circuit includes an Arduino microcontroller, two LEDs (light emitting diodes), resistors, and a Piezo buzzer. It is important for students to understand that to create a closed circuit, we have to attach each piece of hardware so that there is a clear traceable path through which the electricity can flow. In Tinkercad, pieces of hardware are connected by clicking on one piece and then selecting another. 

As they click to make a connection, virtual jumper wires will appear. By default, these are point-to-point connections, but Tinkercad provides the option to add additional nodes (or joints) by double clicking on a wire.  This allows the wires to be "bent" and shaped as needed to organize them and create a clean project.  Students learn that it is easier to understand and diagnose a circuit with clear connections than it is to work with one that looks like a bird's nest!

Lessons that focus on creating the circuit teach students how to connect the different pieces of hardware in order to create a closed, working circuit. This involves a deeper look into what the breadboard does and includes how to connect the resistors and LEDs to the Arduino microcontroller.  Students learn about the anode and cathode of the LED and how the anode must connect to the power source while the cathode must connect to ground.

This impacts the placement of the LED on the breadboard and where the resistors are placed in relation to the LED. This project explores the how-to for circuit set up and explains the basic “why” questions to help students begin to understand how circuits work at an elementary level.

Writing the Code

Students learn how to write code to illuminate red and green LEDs. While most units in Content Library Junior focus on block code, a few introduce the students to text code. Holiday Celebration is one of those where students explore text coding.

But what makes this even more challenging and a greater enriching experience for students is that while most Content Library Junior lessons focused on text code explore the Python programming language, this unit uses C++, the programming language used in Tinkercad and with physical Arduinos. 

Students learn a variety of useful information when learning text code, even if they may not be able to write the program from scratch themselves just yet or explain every step of the program. For example, in the code below, when writing the line that sets redOn equal to 0, students learn that 0 is equivalent to “off.” The word LOW could also have been used in this line to achieve the same goal since the Arduino programming environment defines a constant value assigning LOW to 0.  In programming, constants often serve as aliases for literal values to make the program easier to read, easier to maintain, and easier to extend later with new features.

Conversely, setting redOn to HIGH activates a pin on the Arduino to turn the LED “on,” thus making it light up.  HIGH is another constant whose value has been set to 1.

Additionally, students learn to identify the keywords that comprise the programming language. For example, int stands for “integer,” and it defines the data type for a variable whose value can be a whole number.  The word pin is a variable whose value represents the actual pin on the Arduino to which the other components are connected using jumper wires.  In programming, variables are locations in the computer's memory where information may be stored.

From here, students write code to trigger the Piezo buzzer to play a melody.  This involves cycling the pin to which the Piezo's anode (e.g., positive pin) is connected very fast and at a specific frequency. The concept is the same as with any stringed musical instrument.  When a string vibrates at certain frequencies, we hear distinct musical notes.  Likewise, with the Piezo, the electrical current flexes a crystal with a small metal plate glued to it.  The flexing creates a sharp popping sound like that made with a dog training clicker.  We include a frequency conversion chart for students to help them identify the numbers to use in their programs to generate the notes. With this, students are not only being introduced to electrical circuits and computer programming, but they also get a bit of music theory as well!  Exposing students to a new programming language, showing them how to set up a circuit with different pieces of hardware, and, finally (as we’ll explore in more detail below), reading music, makes for a unit rich with new skills and a variety of concepts that help develop students’ critical thinking and programming skills. 

Incorporating Music

In order to write a program that plays a melody, we spend some time exploring the musical notes for “Let It Snow” and discussing the frequency conversion chart for these notes. Some of our other units also teach the basics of how to read sheet music, while others explore writing music using different programs like Sonic Pi. 

Let's look at some of the ways you might use this project to incorporate music into your curriculum.

Music Challenge

All of our units weave together skills from multiple academic disciplines in order to help students become better problem solvers. You could use Holiday Celebration as a follow up to Play Me a Song, another in which we explore music through block coding, text coding in multiple languages, and reading sheet music. This is a great activity to add to any curriculum looking to emphasize or incorporate music skills.

Holiday Motivation

This is an excellent activity if you are looking to encourage your students to try more STEM-based challenges, but want them to feel motivated to do so. Often holiday challenges and holiday-themed activities bring out excitement in students, and, when they are interested in a project, they usually remain engaged. Holiday Celebration is the perfect activity for developing students' critical thinking skills even when holiday distractions may be all around.

Engineering Challenge

For students motivated by engineering and electronics, this is one of multiple engineering activities you’ll find in Content Library Junior. Activities such as At The Pumpkin Patch (another found in the Seasonal Creations module) and Dream World also introduce very basic circuits operated both without and with code. This module adds in the Piezo buzzer and multiple LEDs, thus elevating the engineering challenge from other modules.

Need help?

Still unsure about teaching this activity or having your students explore this project? Let us know how we can help! Be sure to contact us with your questions. We are excited to help you get your students started with this unit and others that promote STEM thinking. Be sure to head to our website and sign up for a free trial of our Content Library. Happy Holidays!