# line of fire lesson

Create a game that relies on precise instincts and timing reflexes #if #.

## Topic

Functions

## Quick Links

* [tutorial](/lessons/line-of-fire/tutorial)
* [quiz](/lessons/line-of-fire/quiz)
* [quiz answers](/lessons/line-of-fire/quiz-answers)

## 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 pong game using functions, global variable forever loop, global variables, Boolean, for loop, input on button pressed, if statements, as well as simple commands, such as plot, unplot and pause.

## Documentation

* **function** : [read more...](/js/function)
* **return** : [read more...](/js/return)
* **call** : [read more...](/js/call)
* **global variable** : [read more...](/js/data)
* **arithmetic operator** : [read more...](/reference/types/number)
* **Boolean** : [read more...](/reference/types/boolean)
* **forever** : [read more...](/reference/basic/forever)
* **on button pressed** : [read more...](/reference/input/on-button-pressed)
* **if** : [read more...](/reference/logic/if)
* **clear screen** : [read more...](/reference/basic/clear-screen)
* **show string** : [read more...](/reference/basic/show-string)
* **plot** : [read more...](/reference/led/plot)
* **unplot** : [read more...](/reference/led/unplot)
* **pause** : [read more...](/reference/basic/pause)

## Objectives

* learn how to create a function as a unit of code that performs a specific task and returns a result
* learn how a return statement exits a function and returns a value to the code
* 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 arithmetic operators operate on numbers and return a number
* learn how a Boolean type has one of two possible values: true or false
* learn how to repeat code in the background forever
* learn how to conditionally run code depending on whether a condition is true or not
* learn how to run code when an input button is pressed
* learn how to show a string on the @boardname@'s LED screen
* learn how to turn on a LED light on the LED screen. Learn how to specify which LED using x, y coordinates
* learn how to turn off a LED light on the LED screen. Learn how to specify which LED using x, y coordinates
* learn how to pause your code for the specified number of milliseconds

## 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)

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

## Activity

* time: 20 min.
* [tutorial](/lessons/line-of-fire/tutorial)

## Extended Activity

* time: 20 min.
* [quiz](/lessons/line-of-fire/quiz)

## Homework

* Extended Activity: [quiz](/lessons/line-of-fire/quiz)