THE D.C. COUNCIL just completed one of the most disappointing sessions on record, memorable more for the misconduct of its members than for any of its (lackluster) accomplishments. So we hope the start of 2013 — with the addition of a promising at-large member and plans for an improved committee structure — will usher in a chapter of government in which the only ambitions that matter are those of a growing city.

Wednesday will signal the start of the 20th council session, with new at-large member David Grosso (I) taking the oath of office alongside five returning incumbents. There is no question that Mr. Grosso, who ran on a promise of government and campaign reform, is an improvement over the ethically challenged Michael A. Brown, whom he replaces. The new session also affords Chairman Phil Mendelson (D) the opportunity to imprint the council with a better sense of mission.

Mr. Mendelson, elected to fill out the two years left when former chairman Kwame R. Brown was forced to resign in disgrace, has proposed a restructuring of committee assignments that will be subject to council approval. Most welcome is Mr. Mendelson’s decision to create a stand-alone education committee, chaired by the capable David A. Catania (I-At Large). The recent practice of handling education matters in the Committee of the Whole, on which every council member serves and could grandstand, was not working. It will be important for the new committee, which appropriately includes members from the wards most urgently in need of better schools, to provide support for and oversight of education reform without trying to micromanage the work of school or Gray administration officials.

The selections of Muriel Bowser (D-Ward 4) to head the all-important committee on economic development and Tommy Wells (D-Ward 6) to chair the judiciary committee are also good choices.

We, like the Examiner’s Jonetta Rose Barras, were disappointed that Mr. Grosso, given his valuable background as a council and congressional aide, was not given the opportunity to chair a committee. No doubt Mr. Mendelson wanted to cut down on what we agree is an excessive number of council committees, but he should have based the choices of chairmen on merit rather than the political consideration of not wanting to slight longtime colleagues.

The council will also vote Wednesday to establish rules. Whether the vote prohibits the noxious practice of council members and staff using personal e-mail accounts for government business — something Mayor Vincent C. Gray (D) has banned in the executive branch — will be a first test of whether 2013 brings real change or just more of the same.