Mayor Brandon Johnson made his 11th and final school board appointment Tuesday, two months after naming 10 others to the 21-member board.

His new appointee, Cydney Wallace, works for the Cook County court clerk’s office and is board vice president of the Jewish Council on Urban Affairs, according to a spokesperson for the social justice organization. She is a mother of four, and several of her children attend Chicago Public Schools.

Wallace comes to the board at a critical time, as teachers are in the middle of contract negotiations. The district settled this year’s budget without accounting for either the costs of the new teachers contract or a $175 million pension payment to the city. The board’s president has scheduled budget hearings — mandated by law — in March to assess its financial options.

“(Wallace) knows the political waters she’s swimming in,” said Jonathan Elbaz, the Jewish Council’s director of communications and engagement, who has known her for about six years. “She’s a really great activist, relationship builder and community organizer.”

Wallace lives in the Chicago Lawn neighborhood, according to public records. She will represent the largely South and Southwest Side District 8 along with elected board member Angel Gutierrez.

One elected and one appointed board member must represent each of the city’s 10 school board districts, according to state law. In mid-December, Johnson announced 10 appointees, including a board president, to join 10 newly elected members. He left the District 8 seat unnamed.

The board has met several times since without its final member. The mayor’s office attributed the delay in the appointment to the position being an unpaid and demanding.

Chicago’s school board garnered national attention this fall for its transition to a hybrid body in the first public school board election in decades. By 2027, all 21 seats will be elected.

But the school board also made national headlines because of a drawn-out leadership struggle between the mayor — a former teacher who ran for office backed by the Chicago Teachers Union — and CPS schools’ chief Pedro Martinez.

The previous board resigned en masse in October after Martinez refused to take out a $300 million high-interest loan to cover a budget gap created by the unaccounted-for costs of the new teachers contract and pension payment.

Chicago Tribune’s Jake Sheridan contributed.