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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 lesson focus, as part of a series, will be introducing and consolidating the student's knowledge and practical application of abstraction. The notion of abstraction is central to computing, but not always easy for students to grasp.  The intention is to look at it in novel and understandable ways to make sure it is firmly understood

Lesson Links: 1, 2, 3, 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 abstraction, programming language, instruction, open source, digital, file types These words need to be reinforced throughout the series of lessons  
Assessment

Develop abstractions to represent physical objects

Use data patterns to represent physical objects

Evidence can be provided here by showing the development of a drawing working from the abstract, i.e. shapes, to the concrete, a recognizable item.

Equally, evidence that students can work with patterns and understand why we need abstraction to make sense of the world.  For example the symbols on a weather map or even the abstraction of their time-table.

 
Key Questions Some questions to get learners thinking about the topics There are some potentially difficult ideas here, but it should be possible to gently build on their understanding through clear worked examples Why do we use something like "abstraction"?  What is reduction?  Why is abstraction important, for example in weather forecasting?
Learning Objectives
  • To understand the key aspects of abstraction and be able to give examples of how and where it is used
  • To describe and explain, with examples, how data patterns and objects can be used to represent physical objects
Abstraction here will be an introduction to show that they may already be using it on other areas.  An abstraction is an idea that is not related to something concrete, but can be used to think about the concrete thing more freely.  For example, they may have experimented with abstract art in their art lessons, where colours and shapes are said to represent something more familiar. 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
  • Introduction to some examples of abstraction in the wider world, including a chance for student discussion on their understanding so far
  • A teacher led demonstration of using a graphics program to abstract an object
  • Students can break into groups and work on their own examples of abstraction
  • Class discussion and evaluation of the wider uses of abstraction
  • Summarize the key points and reinforce the importance of abstraction and representation

In this lesson we need to consolidate how abstraction helps us better work with a number of elements and how it can shape ideas in a more manageable way.

If you have time, you could carry out a left brain test.  Hand out a picture of a face, get half the class to draw the picture right way up, half to draw it upside down.  Studies show that when we invert a familiar object (ie. face) we then abstract it and can draw lines to represent it, rather than, "I can't draw faces".  This should be a quick way to show abstraction and it's value.

Lessons from the previous session will still be used here.

The main focus of the lesson here should be to play with aspects of abstraction to reinforce how useful it can be.

Assuming they have a good understanding, they can work in groups and then share their findings.

Lesson Structure Possible timings
  1. refresh the topic of abstraction
  2. check pupils understanding, perhaps a quick quiz (handout or learning site based) or verbal check
  3. class based instruction and discussion on using data patterns to represent other objects using bitmap program
  4. group work to work on some of their own possible designs.  Share god examples as the lesson progresses to reinforce abstraction.
  5. discuss what they have learned and what they can apply
  6. volunteers to share their work and explain how abstraction works
  7. highlight next week's focus and issue homework

It would be useful before hand to have a vector based drawing program such as Inkscape logo added to your network

In the previous activities the picture was built from objects (shapes) now build a picture from dots.

Data patterns to make pictures and images. Magnifying glass and newspaper images, red, green and blue dots to make up all colours in the picture. 

Use graph paper to get students to work out how to make letters, with numbers such as 0 for black and 255 for white.  What letters are easy for them to work out?  What letters are bad on e.g. 5  5 graph paper?

Use a piece of squared paper to colour in squares to make a picture. What are the limitations. If we use a piece of graph paper how will it improve the images? It will take longer to make the image – there is more data to put in – but the image will be a better representation of the real thing. Use a bitmap editor such as Wilbur the GIMP icon (similar cloud based version Pixlr), Paintbrush logo (Mac only) Tuxpaint logo to illustrate how pictures can be made up from individual pixels (picture elements).

Use a vector drawing program (Inkscape.org is free with many video tutorials on You Tube)  to build a picture from objects eg make a car using circles and rectangles. Show that you can magnify the shapes as much as you want without them going "grainy".

Opportunities to reinforce abstraction in terms of simplified information representing something more complicated.  Drawing programs like Inkscape are object oriented. They use simple objects to build more complex pictures with the simple objects defined by mathematical formulae. Can use this later to introduce Object Oriented Programing (OOP) where coding objects are used to build more complicated programmes.

There are many Inkscape tutorials on You Tube.  Use these as a starting point.  Students should be very familiar with drawing programs and should pick it up quickly.

Homework Create their own image using graph paper   Students can draw a picture with small squares.  Vary the graph paper size of squares depending on the student's ability.  Cross-reference to pointillism in art.

 

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