Information Technology Reference
In-Depth Information
Why is it warmer than usual?
1.2.2.1.
Heat
by G [2007, Oct 26]
My theory, because with pollution, the ozone layer gradually shrinks each year, so
the sun takes less time to reach the earth, which in return causes the planet to heat
up more rapidly.
1.2.2.1.1.
the Ozone Layer is recovering
by H [2007, Nov 13] Scaffold
Let's put our
knowledge together.
You are right. I just want to add that the ozone layer is gradually
recovering, thanks to our efforts. But, we shouldn't go back to our old habits.
1.3.
Global Warming
by G. [2007, Oct 26] Scaffold
My theory
I think that global warming comes from carbon gas produced by car and truck
motors which evaporates in the atmosphere and causes the planet to heat up.
1.3.1
The Ozone Layer
by H. [2007, Oct 26] Scaffold
New information
It's true. But, we shouldn't forget that if the planet is getting warmer, it's because
the ozone layer is smaller and we have less protection against sunbeams.
1.3.1.1.
Ozone Layer?
by F [2007, Oct 26] Scaffold
Let's put our knowledge
together.
So, if I understand completely, the sunbeams are able to reach the planet's
surface much easier through the holes in the ozone layer. If the sunbeams come in,
then they must surely go back out. What do you think?
1.3.1.2.
You are Right!
by B [2007, Nov 13] Scaffold
New information
It's true, you are right. Because of all the pollution we are making, the ozone layer
is now pierced and we are therefore less protected against sunbeams!
Overall, questioning was an ongoing distributed process rather than first-turn
questions as in the IRF/E structure: Both teachers and students asked ques-
tions but questions differed in their potential to induce explanations. Explanation
was distributed among students, and the above illustration is a clear example
of that.
An Emerging Explanatory Process
Questions asked at one move or another led to a variety of ideas. Progressive dis-
course of an explanatory nature was likely to begin by a note presenting a student's
initial understanding. In the illustrative sequence presented above, a student wrote
on October 26th the following using the scaffold
My theory
: It is that its caused by
heat because it is warmer than usual. Later in November, another student wrote, as
a fifth move, the following note (Fig. 24.5):
Relevant explanations stressed specific problems and their causes. Figure 24.6
is an estimate of the level of explanation, using Hakkarainen's grid, observed in
the sequences according to students' responses. Level 3 is clearly underdeveloped
