(Guest Post by Matthew Ladner)
“Redshirting” children (having children start school at an older age) has become a fad. Some parents have held children back from entering kindergarten with the idea that their child will benefit academically from being older and/or more mature. According to research by Sandra E. Black, Paul Devereux and Kjell G. Salvanes at Vox (an interesting hybrid between a blog and an academic journal for economists) this fad is like many previous education fads: intuitively plausible but actually worthless.
The researchers were able to isolate the impact of late school starting from those of mere age by comparing Norwegian military IQ tests of students born on December 31 to those born on January 1st :
The administrative rule in Norway is that children must start school the year they turn seven. Children born on 31 December start school a year earlier than those born on 1 January – even though they are almost exactly the same age. This provides an exogenous separation between age and school-starting age.
Result: age matters but not school-starting age. Would-be redshirt parents can relax, or more likely, seek an edge some other way.
Posted by matthewladner 
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