For years the D.C. public schools system was publicly ridiculed for its inability to accurately maintain basic statistics, such as how many students were enrolled in the system. Now it’s the turn of the public charter schools — the alternative schools that were supposed to show the traditional public schools how education is done right — to have trouble with their stats.

Back in the 1990s, story after story related how D.C. schools officials had trouble with data systems because, in part, of bad computer systems. As a result, they couldn’t know for certain how many students were enrolled or, for that matter, exactly where teachers were employed. I wrote this story about then superintendent Arlene Ackerman, that said:

“Officials long have had trouble with the simplest tasks, such as counting students; the best estimate is 77,000.”

...and...

“Because of faulty data collection systems, she couldn’t provide an accurate count of summer school enrollment until the six-week session was half over.

Flash forward to 2012.

My colleague Bill Turque wrote in this post on his D.C. Schools Insider blog that there is a discrepancy between the data for student expulsions and suspensions reported by the D.C. Public Charter School Board, which oversees charters, and by some of the schools themselves.

At a D.C. Council oversight hearing last week, the charter school board gave a spreadsheet to the council that has different figures for the same statistic — one reported by the schools and the other by the board. For example, the board says that Friendship Collegiate Academy-Woodson, a high school in Ward 7, expelled 102 of 1,231 students — or 8 percent — in 2010-11. The school is listed as having reported only 67 expulsions.

At Tech Prep, a Friendship middle school in Ward 8, the board reported that 35 of 100 students — that’s 35 percent — were suspended for 10 days or more in 2009-10. The school’s tally is listed as 25.

How is the discrepancy explained? A footnote on the spreadsheet says:

“In certain cases, schools reported that their internal data was different to what was reported to PCSB. In these cases, we are providing [sic] both numbers: P=PCSB; S=School.”

Clearly some schools and the charter board aren’t on the same page when it comes to this data, but the question is why. Counting the number of students who are expelled and suspended can’t really be that hard, can it?