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Lesson details

Learning outcome

I can identify different data types and explain how they are processed.

Key learning points

  1. Common data types include integers, floating point numbers, strings, and Booleans.
  2. Casting allows data types to be converted.
  3. Using incorrect data types can cause errors.

Keywords

  • Data type - defines the kind of data a computer can store and the actions you can perform on it

  • Casting - changing the data type of a piece of data from one type to another

Common misconception

The order of instructions in a program doesn't really matter, as long as all the instructions are there.

Computers execute code line by line, in the order it's written. If you change the sequence, you're changing the steps the computer takes, and that will change the output.

Teacher tip

Emphasise the importance of precise language and clear thinking when teaching about program sequence. Consider examples of where sequences are wrong and the effects it can have on the outcomes.

Equipment

Pupils will need access to a device that can edit and run Python programs. Examples in this lesson use the RPF Code Editor https://oak.link/python-editor

Licence

This content is © Oak National Academy Limited (2026), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Lesson video

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Prior knowledge starter quiz

6 Questions

Q1.
What does the term "sequence" mean in programming?

Instructions are skipped randomly.
Instructions are executed backwards.
Correct answer: Instructions are performed from top to bottom in order.
Instructions are chosen at random.

Q2.
What is debugging?

writing new code for a program
rearranging the sequence of code
Correct answer: finding and fixing errors in code
adding new features to a program

Q3.
What happens if the sequence of code is incorrect?

Correct answer: The program may not produce the correct output.
The program will work faster.
The program will automatically fix itself.
The program will stop working permanently.

Q4.
What is the purpose of a program?

to store data permanently
Correct answer: to execute instructions to achieve a specific task
to debug errors in code
to organise files on a computer

Q5.
What is an example of debugging?

Correct answer: fixing a syntax error in the code
running a program without making changes
writing a new program from scratch
rearranging the order of instructions randomly

Q6.
What is an example of a sequence in real life?

washing clothes before putting them in the washing machine
writing a shopping list randomly
skipping steps in a set of instructions
Correct answer: following a recipe step by step

6 Questions

Q1.
What is casting in programming?

changing the sequence of instructions
finding and fixing errors in code
Correct answer: changing the data type of a piece of data
defining the actions you can perform on data

Q2.
What can happen if you use an incorrect data type?

The program runs faster.
Correct answer: The program produces errors.
The program ignores the data.
The program automatically converts the data.

Q3.
What is the term for a sequence of characters stored as data?

Correct Answer: String

Q4.
What is an example of a floating point number?

42
"Hello"
True
Correct answer: 3.14

Q5.
What is the result of casting a string "123" into an integer?

"123"
Correct answer: 123
error
null

Q6.
Which data type represents true or false values?

string
integer
floating point
Correct answer: boolean

To help you plan your 10 computer science lesson on: Common data types, download all teaching resources for free and adapt to suit your pupils' needs...