Conventional wisdom in public education has it that being the superintendent of an urban school system is one of the hardest jobs to keep for more than a few years.

Make that double for St. Louis schools.

Once again, the city school system finds itself searching for new leadership. On Tuesday, the team running things at district headquarters asked Superintendent Diana Bourisaw to re-apply for her job.

She declined

And, once again, the School Board – or, in this case, the state-backed Special Administrative Board — will begin the arduous task of finding a new superintendent.

As they embark on that new search, we look  at who’s had that job in the recent past — six superintendents in the last five years.

Cleveland Hammonds, 1996-2003. The former Birmingham, Ala. superintendent left when a new School Board, elected with help from Mayor Francis Slay, took over.

Bill Roberti, July 2003- July 2004. The former head of Brooks Brothers came to town with an expensive turnaround firm hired to make a more efficient district. Roberti made lots of layoffs,  closed several schools and, with his gruff manner, ruffled plenty of feathers.

Floyd Crues, July-December 2004. The ex-cop and former principal took the reigns from Roberti, only to leave amid allegations that he gave officials pay raises without the board’s knowledge. 

Pamela R. Hughes, December 2004-April 2005. The former Metro High principal took over as interim leader after Crues’ abrupt departure.

Creg E. Williams, April 2005-July 2006. The former Philadelphia schools official was hired after a national search. He left after a new School Board, seeking its own choice at the top, accepted his resignation with a $250,000 buyout.

Bourisaw, July 2006- Spring 2008. Bourisaw, brought into the district by former Board President Veronica O’Brien, decided this week she did not want to keep the position as the state intervention continues.

Who will be the next district chief? We’ll see after another national search.