A learner is presented with two or more identical switches. Only one is actually
plugged in. This arrangement is rich with teaching and learning possibilities.
Obviously what you will do in practice will depend upon the nature of your student's
disability, and your ambitions for her, but here are some practical examples of
the use of dummy switches, selected to demonstrated the range of benefits to the
teacher as well as to the learner.
1) Progressive learning - an example.
Two single 'press' switches are offered to the student. Each has a home-made
yellow paper overlay stuck upon it. The working switch has a large black dot,
the other a small black dot. The student has to identify the correct switch, wherever
it is put, by the size of the dot. After success at this, gradually change the
dot size until the difference is less marked. Later, add a third switch, also
2) Making choices - anexample.
If a learner has not yet demonstrated that she can make choices, set a switch
with a black overlay, and one with a white overlay, in various positions, the
white one, say, being the working switch. Watch the student's behaviour, to see
if she begins deliberately to avoid the wrong switch as she reaches for the right
switch. Challenge her, then, by placing the good switch in a difficult position,
perhaps causing her to reach across mid-line, whilst the dummy switch is set directly
beneath her best hand. When you are sure that she is capable of choosing the right
switch in the majority of trials, you might go on to offer her a 'menu' at mealtimes,
such that she can choose between food and drink, and tell you, by pointing, which
3) Assessment - an example.
Dummy switches can teach us a lot about the quality of vision a learner might
have. Try a red switch and a yellow dummy, and, if the student is successful in
selecting the correct one, replace the overlay on the dummy with one which is
close in colour to that on the red switch. You might discover that eventually
she will not be able to tell one from the other. Try other colours, or shapes
instead of colours. (I mentioned earlier that, by changing the bulb colour in
the output, you might discover some colour preference. We have one lad who will
not bother with a switch system when the reward is a blue light - he appears not
to see it at all.) Again, you might find that the student makes better selections
without her glasses, and this will tell you something about the prescription for
the correction of her vision.
Certainly, if you plan the challenges well, you will glean some useful information
which might help toward the overall visual assessment of your student.