Test your understanding of subroutines (procedures and functions) in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 7 Practice Tasks Task One Example solution: Create a program with three different subroutines (procedures ). One subroutine asks the user their name and prints a response. The second asks for their age and prints a response. The third asks for their favourite colour and prints a response. Remember to write subroutines before the main program. Task Two Create a program that asks a user to input the length of a side in a square. Write a function that takes this value and returns it to be printed. Example solution: Task Three Example solution: Create a program that takes 3 inputs from the user – a name, a villain and a place. Write a function that outputs a story using the user’s answers. Task Four Create a calculator program that uses four different subroutines (add, subtract, multiply and divide). In the main program ask the user to make a choice of which operator to use and then to enter two numbers. Keep looping until the user types stop. Use the 'Using Subroutines as a Menu' section in the 7b to help you. Example solution: ⬅ 7b - Functions 8a - Using Lists ➡

Learn how to create simple programs in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Setting up Python Downloading Python If you are using Python in Computer Science lessons, then your school should already have it downloaded and installed on the school computers. It is a good idea to download it on a home computer too so you can practice outside of lessons. Python is free and can be downloaded from the official website. You should download the most up-to-date version of Python 3. Save the file and then run it to start installing. Official Download Page Using Python When you run the Python application, it will open the shell. This window will display the outputs of any program you have created. Do not type into the shell . Click on the File tab then New File to open the editor. Python Shell - This displays the outputs of your program. Do not write directly into the shell . Python Editor - All code is written into the editor. When you want to test a program press the F5 key (or click the Run tab then Run Module ). The first time you test a program, it will prompt you to save the file. Make sure you save it somewhere you will remember - it is a good idea to create a folder named 'Python' where you can keep all your practice programs. The next page looks at actually creating a program but above shows how code has been typed into the editor and then displayed in the shell. You never need to save the shell window. Also, the editor saves automatically every time you run the program. Opening a Saved Program When you want to re-open and edit a file you have created previously double-clicking on it won't work . Right-click on the file and select Edit with IDLE : https://trinket.io/python/76b41b35c5 1 a - Printing ➡

A simple Python editor using the Skulpt and Code Mirror libraries. Learn how to create simple programs in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Simple Python Editor You can use this simple Python editor below to complete most of the tasks in the CSNewbs Python sections (except colorama and text files ). It includes basic libraries such as random and time . When you're ready, click 'Run Code ' to see the result in the output below . Python Homepage

Learn how to make simple calculations in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 3b - Simple Calculations Simple Calculations in Python You can perform calculations on numbers in Python using the four main operators : print ( 89 + 47) print ( 89 - 47) print ( 89 * 47) print ( 89 / 47) = 136 42 4183 1.8936170212765957 For addition , use the plus sign + To subtract numbers, use the dash symbol – (but not an underscore _ ) For multiplication , use an asterisk * which can be made by pressing Shift and 8 on a typical keyboard. To divide numbers, use a forward slash / (but not a backslash \ ) Use a string and the calculation to make the output user friendly . print ( "53 x 7 =" , 53 * 7) = 53 x 7 = 371 Simple Calculations Task 1 ( + - * /) Print four different simple calculations, using a different operator ( + - * / ) for each. Make the output user friendly by also showing the calculation (not just the answer). Copy the divide symbol here using Ctrl and C : ÷ Example solution: 18 + 35 = 53 18 - 35 = -17 18 x 35 = 630 18 ÷ 35 = 0.5142857142857142 Using Variables in Calculations You can also perform calculations on variables . The example below has the values of the variables pre-written. You need to store the result in a variable . The total variable has been used to store the result of the multiplication. num1 = 12 num2 = 20 total = num1 * num2 print ( "The total is" , total) = The total is 240 The example below allows the user to input values . num1 = int ( input ( "Enter number one: " )) num2 = int ( input ( "Enter number two: " )) total = num1 + num2 print ( "The to ta l is" , total) Enter number one: 21 Enter number two: 82 The total is 103 = Don't leave the user in the dark, better user interfaces are clear and explain what outputted values mean: num1 = int ( input ( "Enter number one: " )) num2 = int ( input ( "Enter number two: " )) answer = nu m1 - num2 print (num1 , "-" , n um2 , "=" , answer) Enter number one: 83 Enter number two: 29 83 - 29 = 54 = Simple Calculations Task 2 ( Divide by 3) Use an input line with int to ask the user to enter a number . Divide the number by 3 and output the result . Example solution: Enter a number: 11 11 divided by 3 is 3.6666666666666665 Simple Calculations Task 3 ( Add 3 Numbers ) Make three input lines using int to ask the user to enter three numbers . Add the numbers together and output the total . Example solution: Enter the first number: 45 Enter the second number: 32 Enter the third number: 19 The total is 96 ⬅ 3a - Data Types Section 3 Practice Tasks ➡

A glossary of important code to be used in Greenfoot, such as random movement, using a counter removing objects and sound. Aimed at the Eduqas / WJEC GCSE specification. Greenfoot Code Glossary Greenfoot Home This code will work for Version 2.4.2 which is used in Component 2 of the 2016 WJEC/Edquas specification . Key Down 270 if (Greenfoot.isKeyDown("right" )) { setRotation(0); move(1); } 180 90 0 Bounce At Edge if (isAtEdge()) { turn(180); } move(1); if (Greenfoot.getRandomNumber(10)<1) { turn(Greenfoot.getRandomNumber(90) - 45); } Random Remove Object if (isTouching(Apple.class )) { removeTouching(Apple.class ); } Play Sound Greenfoot.playSound("pop.wav" ); Stop Greenfoot.stop(); Counter - (Write this code when an object is removed) Counter counter = (Counter) getWorld().getObjects(Counter.class ).get(0); counter.add(1); Stuck? If you start typing but can't remember what commands come next, press Ctrl and Space together to show a list of all possible commands that you can use.

Learn about the differences between wired and wireless networks. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.2a: Wired & Wireless Networks Exam Board: OCR Specification: J277 Watch on YouTube : Wired Networks Wireless Networks Encryption Wired Connections Wireless Connections Wireless connections, such as WiFi or Bluetooth , use no cables but require a wireless network interface card (WNIC ). Wireless connections generally have a slower speed and can be affected by the computer's distance from the wireless router as well as obstacles like walls or bad weather. Wired connections use physical cables , such as copper or fibre optic wires , and require a network interface card (NIC ) to connect to a network. These wired connections use a wired connection protocol - most commonly Ethernet . Restricted Movement Faster More Secure NIC Required Freedom of Movement Slower Less Secure WNIC Required Encryption Wireless connections are less secure and require encryption . Encryption is the process of scrambling data into an unreadable format so that attackers cannot understand it if intercepted during transmission. The original data (known as plaintext ) is converted to scrambled ciphertext using an encryption key . Only at the correct destination will the encryption key be used to convert the ciphertext back into plaintext to be understood by the receiving computer. Q uesto's Q uestions 3.2a - Wired & Wireless Networks: 1. Briefly compare wired and wireless networks in terms of movement , transmission speed , security and required hardware . You could answer this in the form of a table. [ 8 ] 3.1b - Network Hardware & Internet Theory Topics 3.2b - Protocols & Layers

A simple HTML and CSS editor using Code Minrror libraries. Learn how to create simple web pages using HTML. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Simple HTML & CSS Editor This page is under active development.

App Inventor Task 1 & 2 - Basic Apps Basic Program #1 - Colour Changer This quick tutorial will teach you how to create an app that changes the background colour when you press different buttons . See the video: In Designer layout, firstly drag four buttons from the Palette tab on the left side and drop them one at a time on top of each other in the Viewer . In the Components tab, click on each button and press Rename to change the name (this makes it easier to code them later). You don't need to choose these four colours, but it is a good idea to start with these (you can change them later). You should notice that you are only changing the name of the button - not the button on the text; these are two different variables . Now to change the text on each button. Click on a button in the centre then in the Properties tab on the right scroll down to Text and change the text to a colour. When you've changed all four button texts, then you can start to code. Click on the Blocks button in the top right to start adding the code. In the Blocks tab on the left click on each button block (e.g. Red, Blue, Green and Yellow) and drag over a 'when click ' block for each colour. Blocks we put inside of the 'when click' blocks will execute whenever that button is pressed. Grab a set Screen 1 BackgroundColor from the Screen1 section in the Blocks tab and place one underneath each when click block. Then line up the correct colour from the Colors section in the Blocks tab to the relevant button. Program 1 Complete! The easiest way to run an app that you have created at home using App Inventor 2 is to download the free MIT AI2 Companion App on your smartphone from the Google Play Store . At the top of the App inventor program on your computer , click on Connect and AI Companion . This will generate a six-digit code you can type into your phone. If your school has the emulator installed, you can also use this to test your app. Ideas to Improve Your App: Use the when Screen1 BackPressed block from the Screen1 section in Blocks to turn the background colour white when the back button is pressed. The block is shown to the right; you can work out how to use it. Add more buttons for different colours. Try purple, black and orange for example. Change the BackgroundColour (in Properties ) of each button to represent the colour it says. You might need to change the TextColour too for red and blue (see the image to the right). Password Checker Basic Program #2 - Password Checker This quick tutorial will teach you how to create an app that requires a user to enter a correct password . See the video - maximise to see it clearly: Firstly you need to grab a TextBox from the Palette tab on the left and place it in the Viewer. Then drag a Button and a Label . Put them in this order: You need to change the Text for the button in the Properties tab to 'Enter Password'. Click on your text box and delete the Hint Text from the Properties tab. Click on the label and delete the Text from the Properties tab. Don't worry, the label is still there! Now time to code. Open up the Blocks layout by clicking Blocks in the top right. Drag a when Button1 click block into the centre from the Button1 section in Blocks . Drag an if then block from Control within the when Button 1 click block. Click on the blue cog button and, in the new window underneath, drag an else block within the if block. The top part will update by itself. When the button is clicked we want to see if the text in the text box matches what we want it to be. Grab an = block from Logic and connect it to the if block. Then place a TextBox1 Text block from TextBox1 in the first half and a blank " " block from Text in the second half. In the " " block write what you want the password to be. I've chosen pikachu because pikachu is cool. Grab a Set Label1 Text block from Label1 and put one next to then and another next to else. Place a " " block from Text and snap it next to both of those blocks. If the user has entered the password correctly then you want 'Correct Password' to appear. Otherwise, if they have entered anything else , you want 'Incorrect Password' to appear. Program 2 Complete! The easiest way to run an app that you have created at home using App Inventor 2 is to download the free MIT AI2 Companion App on your smartphone from the Google Play Store . At the top of the App inventor program on your computer , click on Connect and AI Companion . This will generate a six-digit code you can type into your phone. If your school has the emulator installed, you can also use this to test your app. Ideas to Improve Your App: Change the password to something different. If the correct password is entered change the background to gree n . If an incorrect password is entered change the background to red . You may want to scroll up to the first program as a reminder. KS3 Home Task 3

Learn about the components of the Central Processing Unit (CPU) and Von Neumann architecture. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). Exam Board: Cambridge OCR 1.1a: The CPU Specification: GCSE - J277 Watch on YouTube : The CPU The function of each CPU component : Control Unit (CU ) Arithmetic Logic Unit (ALU ) Registers Cache What Von Neumann architecture is. What You Need to Know The Central Processing Unit The Central Processing Unit ( CPU ) is the most important component in any computer system. Like many computer components, it is attached to the motherboard . The purpose of the CPU is to process data and instructions by constantly repeating the fetch-execute cycle . CPU Components The Control Unit (CU ) sends signals to control hardware and coordinate the flow of data inside the CPU and across the computer . It also decodes instructions as part of the fetch-execute cycle . The Arithmetic Logic Unit (ALU ) performs mathematical calculations , logical operations and binary shifts . The results of calculations made by the ALU are stored in a register called the accumulator . A register is a temporary storage space for one piece of data , instruction or address . Different registers are used during the fetch-execute cycle . Cache memory stores frequently accessed data and instructions because it is much faster for the CPU to access (fetch from) than RAM . Computer Architecture The way a computer is designed and structured is known as its architecture . A common type of computer architecture is Von Neumann (pronounced Von Noy-man), named after mathematician John Von Neumann . Von Neumann Architecture Instruction Data RAM ADD 53 A computer with Von Neumann architecture stores both program instructions and data in the same memory (RAM ). This is different from other architectures that have an instruction memory and a separate data memory . Instructions (technically called the opcode ) and data (technically called the operand ) are not the same . An instruction is an action to perform and data is the value to be used. For example with the command 'ADD 43 ', ADD is the instruction and 43 is the data . Von Neumann architecture also contains the key CPU components of a control unit , arithmetic logic unit (ALU ), registers and cache memory . Q uesto's Q uestions 1.1a - The CPU: 1a. What does 'CPU ' stand for ? [1 ] 1b. What is the purpose of the CPU ? [ 2 ] 2. Draw a diagram of the CPU , and l abel the four main components . [ 4 ] 3. Describe the purpose of: a. The Control Unit [ 2 ] b. The ALU [ 2 ] c. The registers [ 2 ] d. Cache memory [ 2 ] 4a. Describe the key feature of Von Neumann architecture . [ 2 ] 4b. Explain how an instruction is different to data . [ 2 ] 1.1b - Fetch-Execute Cycle Theory Topics

Learn about algorithms including programming principles, variables and sequencing. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.1: Programming Principles Exam Board: Eduqas Specification: 2020 Problem Solving There are four stages to computational thinking (smart problem solving ). Decomposition is when you break a problem down into smaller tasks so that it is easier to solve . Pattern Recognition is the process of identifying similar patterns within a problem . Abstraction is when you ignore unnecessary information and focus only on the important facts . Algorithms are the final stage as step-by-step rules are created to solve the problem . An algorithm is usually written as psuedocode or presented as a flowchart . Programming Constructs There are three constructs (ideas) of programming that most programs will contain: Sequence Structuring code into a logical, sequential order . Selection Decision making using if statements . Iteration Repeating code , often using for loops or while loops . Variables Large programs are often modular - split into subroutines with each subroutine having a dedicated purpose. Local variables are declared within a specific subroutine and can only be used within that subroutine . Global variables can be used at any point within the whole program . Local variable advantages Saves memory - only uses memory when that local variable is needed - global variables use memory whether they are used or not. Easier to debug local variables as they can only be changed within one subroutine. You can reuse subroutines with local variables in other programs. Global variable advantages Variables can be used anywhere in the whole program (and in multiple subroutines). Makes maintenance easier as they are only declared once. Can be used for constants - values that remain the same. Local & Global Variables Constants A variable is data that can change in value as a program is being run. A constant is data that does not change in value as the program is run - it is fixed and remains the same. An example of a constant in maths programs is pi - it will constantly remain at 3.14159 and never change. π π Counts & Rogue Values When using iteration (looping) the loop must eventually be able to stop. A count is a variable that is used to record the current iteration (loop number). A rogue value is an unexpected value that will cause the loop to end . For example by typing "Stop" into a loop that asks for numbers. Self-documenting Identifiers An efficient program will use variables with sensible names that immediately state their purpose in the program. Using variable names like 'TotalNum' and 'Profit' rather than 'num1' and 'num2' mean that other programmers will be able to work out the purpose of the code without the need for extensive comments. Q uesto's Q uestions 8.1 - Programming Principles: Problem Solving 1. What is meant by 'decomposition '? Why is it important ? [2 ] 2. What does the term 'abstraction ' mean? Why is it important ? [2 ] 3. What is pattern recognition ? [2 ] 4a. What is an algorithm ? [1 ] 4b. What are the two ways of writing an algorithm ? [2 ] Programming Constructs 1. Describe and draw a diagram for the 3 programming constructs . [6 ] Variables 1. What is the difference between local and global variables ? [4 ] 2. Describe two advantages of using local variables . [2 ] 3. Describe two advantages of using global variables . [2 ] 4. What is a constant ? Give an example . [2 ] 5. Why is it important to use self-documenting identifiers when programming? [2 ] 6. What is a count ? What is a rogue value ? [2 ] 7.1 - Language Levels Theory Topics 8.2 - Understanding Algorithms

Learn how to use logical operators in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 4c - Logical Operators AND Operator The AND operator is used to execute certain code if more than one thing is true . AND is commonly used with account logins - both the username AND the password must be correct . The example below requires both a secret word and a secret number to be correct: print ( "To enter you need the secret word and the secret number!" ) word = input ( "What is the secret word? " ) number = int ( input ( "What is the secret number? " )) if word == "solitude" and number == 2011: print ( "Correct! You may enter!" ) else : print ( "Incorrect! Get out of here!" ) If no part or only some of the if statement is true then the indented code will not run : To enter you need the secret word and the secret number! What is the secret word? solitude What is the secret number? 4503 Incorrect! Get out of here! To enter you need the secret word and the secret number! What is the secret word? windhelm What is the secret number? 1021 Incorrect! Get out of here! Only If all parts of the if statement are true will the indented code be executed : To enter you need the secret word and the secret number! What is the secret word? solitude What is the secret number? 2011 Correct! You may enter! Logical Operators Task 1 ( Three Easy Questions) Ask the user three easy questions and print a special response if they get all three correct . Use the and operator to see if their answer for all each of the questions is correct. You must use a unique variable nam e for each of your inputs (it can't be 'answer' for all three, for example). Example solutions: What is the capital of Germany? Berlin What is the chemical formula for water? H20 What year did World War Two end? 1945 You absolute genius! What is the capital of Germany? Vienna What is the chemical formula for water? W20 What year did World War Two end? 1945 Bit awkward, I thought you'd do better... OR Operator The OR operator is used to execute certain code if one of several statements is true . The program below is checking if either a , e , i , o or u were entered. letter = input ( "Enter a letter: " ) if letter == "a" or letter == "e" or letter == "i" or letter == "o" or letter == "u" : print ( "You entered a vowel." ) else : print ( "You entered a consonant." ) Enter a letter: f You entered a consonant. Enter a letter: e You entered a vowel. It is important that you re-write the variable and operator (e.g. letter ==) each time you use 'or' . It will not work if you just write: if letter == “a” or “e” or “i” or “o” or “u”: Logical Operators Task 2 ( Twins?) Ask the user to enter their favourite colour and then ask them their age . If their favourite colour is the same as yours AND their age is the same as yours then print “Snap! Are you my twin?” . If only one of the statements is true (use the OR operator) then print “Spooky! You’re a bit like me.” . Add an else statement to print “We’re not so similar, you and I.” if there's nothing in common. Example solutions: What's your favourite colour? green What's your age? 15 Snap! Are you my twin? What's your favourite colour? blue What's your age? 15 Spooky! You're a bit like me. What's your favourite colour? red What's your age? 16 We're not so similar, you and I. ⬅ 4b - Mathematical Opera tors Sectio n 4 Practice Tasks ➡

Learn about the six main validation checks - range, type, length, format, lookup table and presence. Also, discover three verification checks - double entry, proof-reading and check digits. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.5: Validation & Verification Exam Board: Eduqas Specification: 2020 What are validation and verification checks? Validation is a process to check that data is reasonable or sensible before it is accepted . Verification is the process of checking that data is correct after it has been entered. Validation Checks Range Check Checks data is within a certain range . Age: 34 203 Type Check Checks data is a certain data type . Height (in cm): 182 Two metres Format Check Checks data is entered in a certain way . Date of Birth (DD/MM/YYYY) 25/03/2001 25th March 01 Presence Check Checks that data has actually been entered and not left blank . Password: fluffythecat123 Lookup Table A table of acceptable entries , also known as a list . Length Check Checks the length of the input is within a certain amount. Telephone Number 08323877319 07383 Verification Checks Double Entry Typing in the data twice to make sure there were no spelling errors the first time. Password: fluffythecat123 flufythecat123 Proofreading Checking two copies of data to ensure they are exactly the same . Check Digit Similar to a checksum in a data packet, a check digit is calculated on barcodes to ensure the rest of the numbers are correct . Address: 11 Cherry Lane 11 Cherry Road Confirm Q uesto's Q uestions 8.4 - Validation & Verification: 1. Describe each type of validation check and give an example . a. Range Check [ 3 ] b. Type Check [ 3 ] c. Format Check [ 3 ] d. Presence Check [ 3 ] e. Lookup Table (List) [ 3 ] f. Length Check [ 3 ] 2. For the following data, suggest which validation check would be most suitable and why : a. Password [ 3 ] b. Country of Birth [ 3 ] c. Number of Tickets [ 3 ] d. Weight (in kilograms) [ 3 ] 3. Describe three types of verification check and give an example : a. Double Entry [ 3 ] b. Proofreading [ 3 ] c. Check Digit [ 2 ] 8.4 - Sorting & Searching Theory Topics 9.1 - IDE Tools