In education, as we learn regularly, when a claim seems to good to be true, it is usually too good to be true. (See test scores, Noyes school, District of Columbia.)

Recently, Leslie Jacobs–a founder of the charter takeover in New Orleans–claimed that students in New Orleans had registered graduation rates higher than the state or the nation.

A Louisiana blogger who calls himself Crazy Crawfish found this claim hard to believe. As it happens, this blogger used to work in data analysis at the Louisiana Department of Education.

He tells a cautionary tale. Before you believe the latest miracle story, read this.