New London — The Board of Education approved a $40.8 million budget Thursday night, about a 2.5 percent increase over the current spending plan of $39.9 million.

The budget includes $400,000 for a second guidance counselor at Bennie Dover Jackson Middle School and four new teachers to reduce overcrowding in kindergarten through third-grade classrooms.

Board members Jason Catala and Barbara Major voted against the budget. Earlier in the evening, they objected to the extra money for the additional staff.

In February, the Finance and Audit Committee asked the superintendent to come up with a budget with a 1 percent increase in spending to cover contractual obligations, such as a 1 percent increase in teachers’ salaries.

But Superintendent Nicholas A. Fischer said Thursday that the school and city administrations had an informal agreement that the schools would not bring an increase larger than 1.5 percent to the City Council.

Fischer on Tuesday presented the Finance and Audit Committee with a $40.4 million budget for 2013-14, representing a 1.5 percent increase. Following a public hearing, the committee voted unanimously to increase the proposed budget to hire additional staff.

The City Council has final approval of the school board’s budget. It can add to or cut the proposal but cannot make line-item reductions.

— Kathleen Edgecomb