The Fairfax County School Board chose new leaders Thursday, tapping a veteran member and a relative newcomer to shepherd the region’s largest school system during the coming year.

Ilryong Moon (At Large), the outgoing vice chairman who has served a dozen years on the board, replaced Jane K. Strauss (Dranesville) as chairman. Moon previously led the board in 2006.

Pat Hynes (Hunter Mill), a former Fairfax teacher and lawyer who took office in January, became vice chairwoman.

The two will lead their colleagues in searching for and hiring a superintendent, one of the more critical and far-reaching decisions a school board can make. Current schools chief Jack D. Dale will retire in June 2013.

Strauss initially ran for reelection as chairman Thursday, but withdrew her name from contention after tying Daniel G. Storck (Mount Vernon) — another veteran member who has served since 2004 — in a six-six vote.

Hynes then nominated Moon, who narrowly prevailed against Storck. Ryan McElveen (At Large) said he had looked to both men for guidance, but Moon had been “the utmost mentor.”

Besides McElveen and Moon, others voting in Moon’s favor were Strauss, Hynes, Kathy Smith (Sully), Tamara Derenak Kaufax (Lee) and Ted Velkoff (At Large).