A group of people with a wide-range of experiences dedicated a Saturday to fixing forms. “It’s just so nerdy,” said one participant.

Not bad, D.C., not bad. New data from the 2010 Census shows that the District of Columbia has now reached a 68 percent level of participation, which means 2 percentage points more of us mailed in our Census forms this year than did in 2000. Last we checked a little over a week ago, we were still hovering at 66 percent. The District’s rate of mail-in participation is still below the national average of…