Music Player
Experience: 1st year, 3rd quarter
Practice: Creating computational artifacts, Testing and refining computational artifacts, and Communicating about computing
Concept: Algorithms, Control, Modularity, and Variables
Length: 90+
Overview and Purpose
Coders combine their previous understandings of creating interactive buttons to create a music player with multiple buttons. The purpose of this project is to reinforce understandings of modularity by combining previous understandings within a new context.
Objectives and Standards
Process objective(s):
Statement:
- I will learn how to create a variety of buttons a user can interact with in Scratch.
Question:
- How can we create a variety of buttons a user can interact with in Scratch?
Product objective(s):
Statement:
- I will create a music player app using a variety of buttons a user can interact with.
Question:
- How can we create a music player app using a variety of buttons a user can interact with
Main standard(s):
1B-AP-10 Create programs that include sequences, events, loops, and conditionals
- Control structures specify the order (sequence) in which instructions are executed within a program and can be combined to support the creation of more complex programs. Events allow portions of a program to run based on a specific action. For example, students could write a program to explain the water cycle and when a specific component is clicked (event), the program would show information about that part of the water cycle. Conditionals allow for the execution of a portion of code in a program when a certain condition is true. For example, students could write a math game that asks multiplication fact questions and then uses a conditional to check whether or not the answer that was entered is correct. Loops allow for the repetition of a sequence of code multiple times. For example, in a program that produces an animation about a famous historical character, students could use a loop to have the character walk across the screen as they introduce themselves. (source)
1B-AP-11 Decompose (break down) problems into smaller, manageable subproblems to facilitate the program development process.
- Decomposition is the act of breaking down tasks into simpler tasks. For example, students could create an animation by separating a story into different scenes. For each scene, they would select a background, place characters, and program actions. (source)
Reinforced standard(s):
1B-AP-09 Create programs that use variables to store and modify data.
- Variables are used to store and modify data. At this level, understanding how to use variables is sufficient. For example, students may use mathematical operations to add to the score of a game or subtract from the number of lives available in a game. The use of a variable as a countdown timer is another example. (source)
1B-AP-15 Test and debug (identify and fix errors) a program or algorithm to ensure it runs as intended.
- As students develop programs they should continuously test those programs to see that they do what was expected and fix (debug), any errors. Students should also be able to successfully debug simple errors in programs created by others. (source)
1B-AP-17 Describe choices made during program development using code comments, presentations, and demonstrations.
- People communicate about their code to help others understand and use their programs. Another purpose of communicating one's design choices is to show an understanding of one's work. These explanations could manifest themselves as in-line code comments for collaborators and assessors, or as part of a summative presentation, such as a code walk-through or coding journal. (source)
Practices and Concepts
Main practice(s):
Practice 5: Creating computational artifacts
- "The process of developing computational artifacts embraces both creative expression and the exploration of ideas to create prototypes and solve computational problems. Students create artifacts that are personally relevant or beneficial to their community and beyond. Computational artifacts can be created by combining and modifying existing artifacts or by developing new artifacts. Examples of computational artifacts include programs, simulations, visualizations, digital animations, robotic systems, and apps." (p. 80)
- P5.2. Create a computational artifact for practical intent, personal expression, or to address a societal issue. (p. 80)
- P5.3. Modify an existing artifact to improve or customize it. (p. 80)
Reinforced practice(s):
Practice 6: Testing and refining computational artifacts
- "Testing and refinement is the deliberate and iterative process of improving a computational artifact. This process includes debugging (identifying and fixing errors) and comparing actual outcomes to intended outcomes. Students also respond to the changing needs and expectations of end users and improve the performance, reliability, usability, and accessibility of artifacts." (p. 81)
- P6.1. Systematically test computational artifacts by considering all scenarios and using test cases." (p. 81)
- P6.2. Identify and fix errors using a systematic process. (p. 81)
Practice 7: Communicating about computing
- "Communication involves personal expression and exchanging ideas with others. In computer science, students communicate with diverse audiences about the use and effects of computation and the appropriateness of computational choices. Students write clear comments, document their work, and communicate their ideas through multiple forms of media. Clear communication includes using precise language and carefully considering possible audiences." (p. 82)
- P7.2. Describe, justify, and document computational processes and solutions using appropriate terminology consistent with the intended audience and purpose. (p. 82)
Main concept(s):
Control
- "Control structures specify the order in which instructions are executed within an algorithm or program. In early grades, students learn about sequential execution and simple control structures. As they progress, students expand their understanding to combinations of structures that support complex execution." (p. 91)
- Grade 5 - "Control structures, including loops, event handlers, and conditionals, are used to specify the flow of execution. Conditionals selectively execute or skip instructions under different conditions." (p. 103)
Modularity
- "Modularity involves breaking down tasks into simpler tasks and combining simple tasks to create something more complex. In early grades, students learn that algorithms and programs can be designed by breaking tasks into smaller parts and recombining existing solutions. As they progress, students learn about recognizing patterns to make use of general, reusable solutions for commonly occurring scenarios and clearly describing tasks in ways that are widely usable." (p. 91)
- Grade 5 - "Programs can be broken down into smaller parts to facilitate their design, implementation, and review. Programs can also be created by incorporating smaller portions of programs that have already been created." (p. 104)
Reinforced concept(s):
Algorithms
- "Algorithms are designed to be carried out by both humans and computers. In early grades, students learn about age-appropriate algorithms from the real world. As they progress, students learn about the development, combination, and decomposition of algorithms, as well as the evaluation of competing algorithms." (p. 91)
- Grade 5 - "Different algorithms can achieve the same result. Some algorithms are more appropriate for a specific context than others." (p. 103)
Variables
- "Computer programs store and manipulate data using variables. In early grades, students learn that different types of data, such as words, numbers, or pictures, can be used in different ways. As they progress, students learn about variables and ways to organize large collections of data into data structures of increasing complexity." (p. 91)
- Grade 5 - "Programming languages provide variables, which are used to store and modify data. The data type determines the values and operations that can be performed on that data." (p. 103)
Vocabulary
Algorithm
- A step-by-step process to complete a task. (source)
- A formula or set of steps for solving a particular problem. To be an algorithm, a set of rules must be unambiguous and have a clear stopping point. (source)
Debugging
- The process of finding and correcting errors (bugs) in programs. (source)
- To find and remove errors (bugs) from a software program. Bugs occur in programs when a line of code or an instruction conflicts with other elements of the code. (source)
Event (trigger)
- An action or occurrence detected by a program. Events can be user actions, such as clicking a mouse button or pressing a key, or system occurrences, such as running out of memory. Most modern applications, particularly those that run in Macintosh and Windows environments, are said to be event-driven,because they are designed to respond to events. (source)
- The computational concept of one thing causing another thing to happen. (source)
- Any identifiable occurrence that has significance for system hardware or software. User-generated events include keystrokes and mouse clicks; system-generated events include program loading and errors. (source)
Scripts
- One or more Scratch blocks connected together to form a sequence. Scripts begin with an event block that responds to input (e.g., mouse click, broadcast). When triggered, additional blocks connected to the event block are executed one at a time. (source)
Variable
- A symbolic name that is used to keep track of a value that can change while a program is running. Variables are not just used for numbers; they can also hold text, including whole sentences (strings) or logical values (true or false). A variable has a data type and is associated with a data storage location; its value is normally changed during the course of program execution. (source)
- Variables play an important role in computer programming because they enable programmers to write flexible programs. Rather than entering data directly into a program, a programmer can use variables to represent the data. Then, when the program is executed, the variables are replaced with real data. This makes it possible for the same program to process different sets of data. (source)
More vocabulary words from CSTA
Connections
Integration
- Potential subjects: History, language arts, media arts, music, social studies
- Example(s): This project could connect with history, social studies, and language arts standards if the musical phrases a coder creates or performs are based on historical, contemporary, or fictional music for different time periods or locations. Click here to see other examples and share your own ideas on our subforum dedicated to integrating projects or click here for a studio with similar projects.
Vocations
- There are a wide range of careers in app development that involve coding. In fact, many young coders are creating and selling their own apps for various devices. Click here for an example TED Talk by a 12-year-old app developer. Click here to visit a website dedicated to exploring potential careers through coding.