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Section Title Primary information Description and Notes Suggested resources
Lesson Length The expected lesson length will be approximately one hour

Some variation possible.

Assessment Level 1

Students The lesson is suitable for KS3 and KS4 students Since this is a new specification, the lesson is suitable for Year 7 to 9 students and differentiated by outcome  
Overall Focus The previous lesson introduced logic and how this helps the structure of algorithms.  This lesson will now investigate how to make algorithms better.  In this case, more efficient. This lesson will introduce aspects of efficiency in algorithms

Lesson Links: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39

Key words algorithm, search, sort, logic, efficiency These words need to be reinforced throughout the series of lessons The key meaning here, from Wikipedia is "Roughly speaking, 'acceptable' means: will it run in a reasonable amount of time on an available computer".  

apply logic to efficiency and effectiveness in algorithms

Evidence here will be student's own work and assessor observations  
Key Questions Some questions to get learners thinking about the topics Students do need to know the deep knowledge here, but need to be able to show that they are aware that instructions can be made to be more efficient.  In an emergency situation, excessive instructions, though accurate, might not be the best option. What is efficiency?  Can you give examples of your own life where you use efficiency gains?  What advantages are there to more efficient sets of instructions?  Are there any disadvantages?
Learning Objectives
  • To understand the basics of efficiency
  • To describe and explain, with examples their understanding of efficiency
  • To practise as a class some techniques to improve efficiency

Students need to be shown some efficiency in instructions.

If you are using the Learning Machine learning system, students can add their comments and material to this site as evidence of their growing understanding.  The site, if used consistently, will show progression via charts of activity and outcomes.
Teaching and Learning Elements
  • Overview of efficiency with examples from everyday life
  • Students can break into groups and work on their own examples
  • Class discussion and examples of their own efficiency ideas
  • Group or individual work

In this lesson students need to be shown examples of efficiency and how it helps in solving problems in a timely manner.

Use some of the student's ideas and examples to flesh out a solid understanding before progressing

Question students about how and why they did what they did.  Check for understanding.


Lesson Structure Possible structure
  1. introduce some basic ideas about efficiency with clear examples
  2. show students some more detailed examples of efficiency with data about the improvements made
  3. group work to work on some of their own ideas
  4. discuss what they have learned and what they can apply
  5. volunteers to share their work and explain how they came to their opinions
  6. highlight next week's focus and issue homework

There is also lots of good examples on the BBC logo bitesize pages.

Bad instructions have quite an impact on our lives.  Students need to be able to show an understanding of what makes a set of instructions (algorithms) more efficient and therefore "better".

Some discussions on everyday situations should help to illustrate the importance of efficiency in algorithms.  For example, on their street, what would help the person delivering the post most: a bunch of all of the letters; the letters organised by names; or the letters organised by house number.  Other examples should be easy to come up with.

Homework Get students to work on improving a basic algorithm for efficiency gains.  Give them a list of things (birds, mammals, insects, flowers etc) and ask them for an algorithm to quickly sort them for a characteristic or two. Students can vary their homework depending on their level of understanding Get students to document their experience on their portfolio system for assessment


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