It's called "the summer brain drain" because during those long, hot months away from school, kids supposedly forget a lot of what they had learned in class.
Research, however, tells a more nuanced story: Some learning is lost among some groups, and others gain.
Here's what experts from Johns Hopkins University, the University of Tennessee, the University of Virginia and elsewhere say happens over the summer:
-- Most students -- regardless of family income or background -- lose 2 to 2 1/2 months of the math computational skills that they learned during the school year.
-- Students from low-income homes lose two to three months in reading skills learned in the previous school year.
-- Middle-class students make slight gains in reading achievement as measured on standardized tests.
Those findings suggest the obvious: that children lose math ability when they don't use it and that middle-class students read more than those from poor families because they have more books at home. (The research looked at middle-class kids, but similar results would presumably be found in children from high-income families.)