Diagrammatic aids

5. DIAGRAMMATIC PAPER AIDS

5.1 The diagrammatic aid is illustrative, employing simplified figures or symbols where possible, and containing no extraneous information. There may be a few words or numerals shown but their meaning in the context will not be obvious.

5.2 Two examples which follow are accompanied by typical teacher / class language which will illustrate the two options open to a teacher. In the first example the teacher explains what the aid means. In the second case the teacher gets the class involved in interpreting the information. This involves teacher's questions about the diagrams with students drawing conclusions or suggesting solutions by reference to the information on the chart.

5.3 THE EXPLANATORY APPROACH

Preliminary information: At the Pensicola Research Base a test was conducted using judgement of bank or tilt by blindfolded experienced pilots. (They, of course, were not flying the test plane.)

Symbol indicated during the explanation

Explanation content

Aircraft were banked at angles between 10^o and 60 ^o throughout the series of tests.

Each banking manoeuvre was sustained over a period of 1 minute.

Blindfolded pilots however, reported that the banking sensation ceased after 20 seconds i.e. they reported that the aircraft appeared to be flying again straight and level.

Their judgement of the degree of banking without visual cues ranged from 4 ^o to 12^o. While this judgement was very innacurate, judgement of gravitational forces was unimpaired throughout the tests.

5.4 THE DISCUSSION APPROACH

Here, there is a gradual discovery of content through questioning. The teacher may have to provide some explanation if the students do not interpret the visual clues accurately.

Basic content of teacher's questions

Basic content of students' observations

What differences are there in ship profiles?

Traditional cargo vs container cargo ships. Differences in rigging, storage,cranes. Crane on container ship is able to traverse the full length and width of the vessel.

What factors effect cargo handling and placement for vessel 1?

Cargo is loaded through several hatches; may be loaded with slings, hooks, nets, palettes, by conveyor, pump, driven on or lifted manually. Destination priorities, contents (fragility, need for refrigeration, weight, combustibility etc.), uneven sizes. Loading is often dependent on dock or ship's loading facilities and capacities.

What factors effect cargo handling for the vessel in 2 and 3?

Uniformity of container sizes. Because of strength, reduced danger to fragile contents when containers are stacked. Containers may be customized i.e. refrigerated or heated, padded etc. Secure against theft. Uniform size ensures ease of access for loading.The ship's own crane can transport the cargo along the ship's length, and to and from the ship in conjunction with the port facilities (2) or in the absence of port facilities(3). Trucks can be loaded directly from the ship.

In addition to the student participation in this second approach, the diagrammatic aid overcomes many of the disadvantages listed for the written and pictorial information type.

Because the amount of overt (obvious, recognisable) information is limited, it requires teacher explanation or guided interpretation. If attention wanders, it is retrieved as each new symbol or diagram is explained. Sequences can be emphasised if relevant. Visual recall is assisted by the diagrams but pupils are "forced" to associate details of the explanation with the visuals.
Diagrammatic aids can form the basis for summaries. These can be copied by the students into their books.
Diagrammatic aids offer excellent opportunities for revision through(i) Pupil oral re-explanation (ii) Pupil written re-explanation(iii) Pupil oral or written answers to teacher questioning.

Unlike the written and pictorial information aid, the diagrammatic chart is of little use for reference because it is no longer self explanatory.

Its additional factors in improving teacher effectiveness more than compensate for this however.

A final advantage to consider is that the teacher using a diagrammatic aid (especially a borrowed example) is forced to research the subject matter thoroughly so that the explanation or discussion will be clear and accurate.

Links to

Introduction to a classification of Paper Aids
Written and Pictorial Information
Progressive labelling
Progressive assembly
Summing Up

Return to Nev Goodwin's Home Page

*Symbol indicated during the explanation*	*Explanation content*
	Aircraft were banked at angles between 10^o and 60 ^o throughout the series of tests.
	Each banking manoeuvre was sustained over a period of 1 minute.
	Blindfolded pilots however, reported that the banking sensation ceased after 20 seconds i.e. they reported that the aircraft appeared to be flying again straight and level.
	Their judgement of the degree of banking without visual cues ranged from 4 ^o to 12^o. While this judgement was very innacurate, judgement of gravitational forces was unimpaired throughout the tests.

*Basic content of teacher's questions*	*Basic content of students' observations*
What differences are there in ship profiles?	Traditional cargo vs container cargo ships. Differences in rigging, storage,cranes. Crane on container ship is able to traverse the full length and width of the vessel.
What factors effect cargo handling and placement for vessel 1?	Cargo is loaded through several hatches; may be loaded with slings, hooks, nets, palettes, by conveyor, pump, driven on or lifted manually. Destination priorities, contents (fragility, need for refrigeration, weight, combustibility etc.), uneven sizes. Loading is often dependent on dock or ship's loading facilities and capacities.
What factors effect cargo handling for the vessel in 2 and 3?	Uniformity of container sizes. Because of strength, reduced danger to fragile contents when containers are stacked. Containers may be customized i.e. refrigerated or heated, padded etc. Secure against theft. Uniform size ensures ease of access for loading.The ship's own crane can transport the cargo along the ship's length, and to and from the ship in conjunction with the port facilities (2) or in the absence of port facilities(3). Trucks can be loaded directly from the ship.