# digital pet lesson

a display of pet images for the @boardname@.

## Topic

Functions

## Quick Links

* [tutorial](/lessons/digital-pet/tutorial)
* [quiz](/lessons/digital-pet/quiz)
* [quiz answers](/lessons/digital-pet/quiz-answers)
* [challenges](/lessons/digital-pet/challenges)

## Class

Year 7

## Prior learning/place of lesson in scheme of work

Learn how to create **functions**, `function()` that perform a specific task and returns a result. We will be learning how to create a digital pet app using functions, global variables, forever loop, input button in pressed, input on shake as well as simple commands, such as show string, show number, and pause.

## What the teacher needs to know

* Algorithm: An unambiguous set of rules or a precise step-bystep guide to solve a problem or achieve a particular objective.
* Command: An instruction for the computer to execute, written in a particular programming language.
* Data: A structured set of numbers, possibly representing digitised text, images, sound or video, which can be processed or transmitted by a computer, also used for numerical (quantitative) information.
* Hardware: The physical systems and components of digital devices; see also software.
* Input: Data provided to a computer system, such as via a keyboard, mouse, microphone, camera or physical sensors.
* Output: The information produced by a computer system for its user, typically on a screen, through speakers or on a printer, but possibly through the control of motors in physical systems.
* Programmable toys: Robots designed for children to use, accepting input, storing short sequences of simple instructions and moving according to this stored program.
* Program: A stored set of instructions encoded in a language understood by the computer that does some form of computation, processing input and/or stored data to generate output.
* Script: A computer program typically executed one line at a time through an interpreter, such as the instructions for a Scratch character.
* Selection: A programming construct in which one section of code or another is executed depending on whether a particular condition is met.
* Sequence: To place program instructions in order, with each executed one after the other.
* Simulation: Using a computer to model the state and behaviour of real-world (or imaginary) systems, including physical or social systems; an integral part of most computer games.
* Variables: A way in which computer programs can store, retrieve or change data, such as a score, the time left, or the user’s name.

**QuickStart Computing Glossary

## Documentation

* **function** : [read more...](/js/function)
* **call** : [read more...](/js/call)
* **global variable** : [read more...](/js/data)
* **assignment operator** : [read more...](/reference/variables/assign)
* **forever** : [read more...](/reference/basic/forever)
* **button is pressed** : [read more...](/reference/input/button-is-pressed)
* **show string** : [read more...](/reference/basic/show-string)
* **show number** : [read more...](/reference/basic/show-number)
* **create image** : [read more...](/reference/images/create-image)
* **show image** : [read more...](/reference/images/show-image)
* **pause** : [read more...](/reference/basic/pause)

## Resources

* Activity: [tutorial](/lessons/digital-pet/tutorial)
* Activity: [quiz](/lessons/digital-pet/quiz)
* Extended Activity: [challenges](/lessons/digital-pet/challenges)

## Objectives

* learn how to create a function as a unit of code that performs a specific task and returns a result
* learn how to call an existing function in your script
* learn how to create a global variable as a place where you can store data so that you can use it later in your code, accessible across functions and in nested code blocks
* learn how to set or change the value of a global variable
* learn how to repeat code in the background forever
* learn how to get the state of an input button
* learn how to show a number on the @boardname@'s LED screen
* learn how to show a string on the @boardname@'s LED screen
* learn how to create an image to show on the @boardname@'s LED screen
* learn how to show an image on the @boardname@'s LED screen
* learn how to pause your code for the specified number of milliseconds

## Links to the National Curriculum Programmes of Study for Computing

## Progression Pathways / Computational Thinking Framework

#### Algorithms

* Designs solutions (algorithms) that use repetition and two-way  selection, ie if, then and else.(AL)
* Uses diagrams to express solutions.(AB)
*  Uses logical reasoning to predict  outputs, showing an awareness of inputs (AL)
* Represents solutions using a structured notation (AL) (AB)

#### Programming & Development

* Creates programs that implement algorithms to achieve given goals (AL)
*  Declares and assigns variables(AB)
* Uses post-tested loop e.g.‘until’,and a sequence of selection statements in programs,including an if,then and else statement(AL)
* Understands the difference between, and appropriately uses if and if, then and else statements(AL)
* Uses a variable and relational operators within a loop to govern termination (AL) (GE)
* Uses a range of operators and expressions e.g. Boolean, and applies them in the context of program control. (AL)
* Selects the appropriate data types(AL) (AB

#### Data & Data Representation

* Defines data types: real numbers and Boolean (AB)

#### Communication Networks

* Demonstrates responsible use of technologies and online services, and knows a range of ways to report concerns Understands how search engines rank search results (AL)

#### Information Technology

* Collects, organizes, and presents data and information in digital content (AB)
* Makes appropriate improvements to solutions based on feedback received, and can comment on the success of the solution (EV)
* Uses criteria to evaluate the quality of solutions, can identify improvements making some refinements to the solution, and future  solutions (EV)

Computational Thinking Concept: AB = Abstraction; DE = Decomposition; AL = Algorithmic Thinking; EV = Evaluation; GE = Generalisation

## Activity

* time: 20 min.
* [tutorial](/lessons/digital-pet/tutorial)
* [quiz](/lessons/digital-pet/quiz)

## Extended Activity

* time: 20 min.
* [challenges](/lessons/digital-pet/challenges)

## Homework

* Extended Activity: [challenges](/lessons/digital-pet/challenges)

## Intended follow on

Publish script to the classroom.

