Information and communication technologies in schools: a ...

An Agent is capable of performing a set of commands given by a child – for
example, to move across the screen, make turns, and leave a trace of its movements.
In a sense, the child is training the Agent to perform quite complex tasks.
A specific example is the Robot-in-Maze microworld. The maze is a labyrinth
usually within the boundaries of a rectangular grid. An Agent called Robot has a
limited set of elementary sensors such as the ability to see or feel a wall in front of
it and a repertory of predetermined actions like, for instance, head North. A large
set of tasks can be given to the student. The first tasks begin simply with, for
example, the maze as an empty rectangle. Further tasks can bring a student to
sophisticated issues of structural algorithm design. Students can immediately see
the execution of their plan on the computer screen.
Another well-known example is the Turtle microworld. An Agent called,
and looking very much like a, Turtle can move forward any specified distance,
turn to any specified angle, draw geometric figures, and change shape and
colour. The most important example of a Turtle microworld is the Logo family.
In fact, some of the Logo languages combine the idea of microworlds with
general applications components (text, graphics and sound editors) and general
office applications.
Let us describe the main educational advantages of microworlds, which are
evident even in the most basic forms.
Being in command motivates learning activity
A teacher begins by showing students how an Agent can be made to move by typing
commands at a keyboard or by clicking pictorial icons and setting sliders,
determining kinds, directions and parameters of the Agent’s movements. For
example, typing FORWARD 100 makes an Agent move in a straight line a distance
of 100 Agent steps of one millimetre each. Typing RIGHT 90 causes the
Agent to pivot in place through 90 degrees. Typing PENDOWN causes the
Agent to lower a pen in order to leave a visible trace of its path while PENUP
instructs it to raise the pen and leave no trace. Students need to explore a great
deal before gaining mastery of these steps but the task is engaging enough to
carry most children through this stage of learning.
Since learning to control the Agent is like learning a language, this activity
mobilizes the student’s expertise and pleasure in speaking. Since it puts the student
in charge, it also mobilizes the student’s expertise and pleasure in commanding.
To make an Agent trace a square, you walk in a square yourself and
ICT in Learning and Teaching
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