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Question:  My 6th graders are about to start their inter stellar/planetary
studies.  Subject: Land mass distribution at the beginning
If the Earth formed out of the primordial gas cloud, one would expect that
the continents would be dispersed in a balanced configuration as the Earth
cooled.  However modern theory places them together in a large land mass
or "super continent, seemingly in an out of balanced state.  How did this
happen?
groovey

Answer:  Wonderful question! I'm going to quote from two texts ["Pangaea" is the 
name given to the "supercontinent" which, it is believed, broke apart,
over 200 million years ago, into pieces which drifted apart and became the
present-day continents] :
From "The Solar System" by Encrenaz and Bibring, p. 135:
"It is now possible to follow the history of the destruction of Pangaea and
geological evolution that was a result. On the other hand, we have hardly
any information about the continents that existed before that phase when
there was just one: did Pangaea appear as a result of the incessant move-
ment of the continents, shortly before the break-up, or had it existed as
a stable entity for thousands of years? From what we know of the causes of
continental drift, the first possibility seems more likely."
From "Exploration of the Universe" by Abell, Morrison, and Wolff, pp.262-3:
"If we extrapolate the plates' motion backward we arrive, some 200 million
years ago, at the supercontinent of Pangaea... The configuration of the
continents before Pangaea is less well understood. It is clear that plate
tectonics were at work, from the existence of old mountains (such as the
Urals in the U.S.S.R. and the Appalachians in the U.S.) that were formed
more than 200 million years ago. Recent studies indicate that plate tec-
tonic activity in what is now North America can be traced back 1.5 billion
years."
In other words, it is believed that Pangaea was not the original land-
mass configuration, but there are no guesses about how it came to be.
rcwinther