Former Minneapolis school superintendent Carol Johnson is stepping down as chief of Boston public schools, the district announced Wednesday.

Johnson said her decision came after the "life-altering" death in March of her husband and best friend , educator Matthew Johnson.

She said she will step down at the end of the current school year.  That will give her nearly six years in the post, or about the same time she headed Minneapolis schools between 1997 and 2003.  

Johnson left Minneapolis to head Memphis schools, which has three times as many students.  But she left there after four years for the more prestigeous post heading schools in a major East Coast city.

Among the Minneapolis leaders she mentored and brought to Memphis with her were Minnesota Education Commissioner Brenda Cassellius, Minneapolis Superintendent Bernadeia Johnson, Michael Goar of the Generation Next organization.

The decision was considered a surprise in the Boston area.