TOpic 4 the right order
English National Curriculum:
Key Stage 1
Tooltip content
learning objectives
Tooltip content
to understand the process of ordering (sequencing).
success criteria
  • I can explain why an order matters.
  • I can put a set of actions into the right order.
  • I can perform actions in the right order to solve problems.
top tips
  • An order can contain any number of actions but no actions can be skipped in the order.
  • The order of  the actions is used to solve problems.
Common misconceptions


Sequential Execution

A sequence is a basic algorithm in computer programming. It is a set of logical steps carried out in order. Actions in a sequence are like steps in the right order.

Sequential execution means an action leads to the next action in a correct order. Programs start by executing the first statement and continue by executing statements in sequence. We can think of this as doing things in the right order, like putting on our socks before our shoes.

Computer programs run with a strict order of events. Like reading a book, each line is run in sequence one after the other. It is there fore important for a program to be built with an order of events in mind. A login system would be no good if it checked your credentials after it had allowed you access, one event must come before the other.

This can often be referred to as a sequence. A sequence is a set of actions that is completed in a specific order. Action 1 is performed, then Action2, then Action 3, etc, until all of the actions in the sequence have been carried out.

Sequences are one of  the base elements of building computer algorithms and are fundamental to understanding how code should written and read. They also link to learning about debugging; having your sequence out of order will produce a computer bug. In order to find and fix the bug it is necessary to discover which step of the algorithm is out of order and work out what needs to be changed to make the algorithm run correctly.