Search the California Content Standards

Standard:
Justify the selection of specific control structures by identifying tradeoffs associated with implementation, readability, and performance.

Descriptive Statement:
The selection of control structures in a given programming language impacts readability and performance. Readability refers to how clear the program is to other programmers and can be improved through documentation. Control structures at this level may include, for example, conditional statements, loops, event handlers, and recursion. Students justify control structure selection and tradeoffs in the process of creating their own computational artifacts. The discussion of performance is limited to a theoretical understanding of execution time and storage requirements; a quantitative analysis is not expected. For example, students could compare the readability and program performance of iterative and recursive implementations of procedures that calculate the Fibonacci sequence. Alternatively, students could compare the readability and performance tradeoffs of multiple if statements versus a nested if statement.

Standard:
Iteratively design and develop computational artifacts for practical intent, personal expression, or to address a societal issue by using events to initiate instructions.

Descriptive Statement:
In this context, relevant computational artifacts can include programs, mobile apps, or web apps. Events can be user-initiated, such as a button press, or system-initiated, such as a timer firing. For example, students might create a tool for drawing on a canvas by first implementing a button to set the color of the pen. Alternatively, students might create a game where many events control instructions executed (e.g., when a score climbs above a threshold, a congratulatory sound is played; when a user clicks on an object, the object is loaded into a basket; when a user clicks on an arrow key, the player object is moved around the screen).

Standard:
Systematically design programs for broad audiences by incorporating feedback from users.

Descriptive Statement:
Programmers use a systematic design and review process to meet the needs of a broad audience. The process includes planning to meet user needs, developing software for broad audiences, testing users from a cross-section of the audience, and refining designs based on feedback. For example, students could create a user satisfaction survey and brainstorm distribution methods to collect feedback about a mobile application. After collecting feedback from a diverse audience, students could incorporate feedback into their product design. Alternatively, while developing an e-textiles project with human touch sensors, students could collect data from peers and identify design changes needed to improve usability by users of different needs.

Standard:
Explain the limitations of licenses that restrict use of computational artifacts when using resources such as libraries.

Descriptive Statement:
Software licenses include copyright, freeware, and open-source licensing schemes. Licenses are used to protect the intellectual property of the author while also defining accessibility of the code. Students consider licensing implications for their own work, especially when incorporating libraries and other resources. For example, students might consider two software libraries that address a similar need, justifying their choice of one over the other. The choice could be based upon least restrictive licensing or further protections for their own intellectual property.

Standard:
Iteratively evaluate and refine a computational artifact to enhance its performance, reliability, usability, and accessibility.

Descriptive Statement:
Evaluation and refinement of computational artifacts involves measuring, testing, debugging, and responding to the changing needs and expectations of users. Aspects that can be evaluated include correctness, performance, reliability, usability, and accessibility. For example, after witnessing common errors with user input in a computational artifact, students could refine the artifact to validate user input and provide an error message if invalid data is provided. Alternatively, students could observe a robot in a variety of lighting conditions to determine whether the code controlling a light sensor should be modified to make it less sensitive. Additionally, students could also incorporate feedback from a variety of end users to help guide the size and placement of menus and buttons in a user interface.

Standard:
Design and develop computational artifacts working in team roles using collaborative tools.

Descriptive Statement:
Collaborative tools can be as complex as a source code version control system or as simple as a collaborative word processor. Team roles in pair programming are driver and navigator but students can take on more specialized roles in larger teams. Teachers or students should choose resources that aid collaborative program development as programs grow more complex. For example, students might work as a team to develop a mobile application that addresses a problem relevant to the school or community, using appropriate tools to support actions such as: establish and manage the project timeline; design, share, and revise graphical user interface elements; implement program components, track planned, in-progress, and completed components, and design and implement user testing.

Standard:
Document decisions made during the design process using text, graphics, presentations, and/or demonstrations in the development of complex programs.

Descriptive Statement:
Complex programs are often iteratively designed as systems of interacting modules, each with a specific role, coordinating for a common overall purpose. Comments are included in code both to document the purpose of modules as well as the implementation details within a module. Together these support documentation of the design process. Students use resources such as libraries and tools to edit and manage parts of the program and corresponding documentation. For example, during development of a computational artifact students could comment their code (with date, modification, and rationale), sketch a flowchart to summarize control flow in a code journal, and share ideas and updates on a white board. Students may document their logic by explaining the development process and presenting to the class. The presentation could include photos of their white board, a video or screencast explaining the development process, or recorded audio description.

Standard:
Translate between different representations of data abstractions of real-world phenomena, such as characters, numbers, and images.

Descriptive Statement:
Computers represent complex real-world concepts such as characters, numbers, and images through various abstractions. Students translate between these different levels of data representations. For example, students could convert an HTML (Hyper Text Markup Language) tag for red font into RGB (Red Green Blue), HEX (Hexadecimal Color Code), HSL (Hue Saturation Lightness), RGBA( Red Green Blue Alpha), or HSLA (Hue Saturation Lightness and Alpha) representations. Alternatively, students could convert the standard representation of a character such as ! into ASCII or Unicode.

Standard:
Describe tradeoffs associated with how data elements are organized and stored.

Descriptive Statement:
People make choices about how data elements are organized and where data is stored. These choices affect cost, speed, reliability, accessibility, privacy, and integrity. Students describe implications for a given data organziation or storage choice in light of a specific problem. For example, students might consider the cost, speed, reliability, accessibility, privacy, and integrity tradeoffs between storing photo data on a mobile device versus in the cloud. Alternatively, students might compare the tradeoffs between file size and image quality of various image file formats and how choice of format may be infuenced by the device on which it is to be accessed (e.g., smartphone, computer).

Standard:
Demonstrate the flow of execution of a recursive algorithm.

Descriptive Statement:
Recursion is a powerful problem-solving approach where the problem solution is built on solutions of smaller instances of the same problem. A base case, which returns a result without referencing itself, must be defined, otherwise infinite recursion will occur. Students represent a sequence of calls to a recursive algorithm and show how the process resolves to a solution. For example, students could draw a diagram to illustrate flow of execution by keeping track of parameter and returned values for each recursive call. Alternatively, students could create a video showing the passing of arguments as the recursive algorithm runs.