minesweeper lesson


Global Variables


Year 7

Prior learning/place of lesson in scheme of work

Learn how to create a minesweeper game with plot, led→plot , unplot, led→unplot, global variables to keep track of the coordinates that the player is selecting. We will be learning how to create a minesweeper game using global variables, if (conditionals), input on button pressed, math random as well as simple commands such as led plot, led unplot, show string, 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.
  • Decomposing: The process through which problems or systems are broken down into their component parts, each of which may then be considered separately.
  • 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.
  • 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




  • 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 return a random number
  • learn how to turn on a LED light on the LED screen
  • learn how to turn off a LED light on the LED screen
  • learn how to run code when an input button is pressed
  • learn how to conditionally run code depending on whether a condition is true or not
  • learn how to show a string of the LED screen one character at a time (scrolling left to right)
  • 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


  • Designs solutions (algorithms) that use repetition and two-way selection, ie if, then and else.(AL)
  • 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)
  • Understands the difference between, and appropriately uses if and if, then and else statements(AL)
  • 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

  • Understands the difference between data and information(AB)
  • Performs more complex searches for information e.g. using Boolean and relational operators(AL) (GE) (EV)

Hardware & Processing

  • Knows that computers collect data from various input devices, including sensors and application software (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)
  • 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