The High Cost Of Teacher Strikes  Optimists hope that the
Chicago teacher strike will end quickly. Perhaps so. But as
Dylan Matthews reports, even short strikes have crushing effects
on vulnerable students.  If the strike happened when a student
was in grade 2 or 3, their scores rose by slightly less. But if
the strike happened when the student was in grade 5 or 6, their
scores rose by a whole lot less. Scores for strike-affected
fifth-graders were a full 3.8 percent lower than those for
fifth-graders in schools and grades not affected. If that
doesn’t seem like much, it’s 29 percent of the standard
deviation (or the typical amount by which students differ from
their class average). Strikes, in other words, accounted for one
third of why some students did better than others.  Remember
that if you hear it said that the teachers are doing it "for the
children."