Different students should have different numbers of marbles (valence electrons) which makes them different from each other.
(Different students; should have; different numbers of marbles (valence electrons) which makes them different from each other) (different numbers of marbles; makes; them different from each other)
Different students different numbers of marbles
should have makes
different numbers of marbles (valence electrons) which makes them different from each other
them different from each other