INDIANAPOLIS — Indiana’s largest school district is poised to close six more schools and lay off as many as 400 teachers in a shake-up that would send thousands of students to different schools.

Indianapolis Public Schools Superintendent Eugene White said he also expects deep cuts in the district’s central office.

“It’s never easy to close schools, but our financial situation demands we make tough decisions,” he said Friday. “We are determined to be good stewards of the public tax dollars.”

White said the school closures would change school boundaries and affect about three-quarters of the district’s elementary schools.

He said current estimates are that all elementary school teachers with fewer than three years of experience would be laid off but that the district would offer a retirement incentive that might reduce the number of layoffs. The district has about 3,000 teachers.

The announcement, which neighborhood leaders said could devastate their communities, came four days before district residents vote on a property tax increase to pay for $278 million in renovations at 32 schools — including the six White wants to now close.

If the School Board approves those closings, the district plans to reduce the $278 million project accordingly.

The 1,700 students attending those six schools will be shifted to other schools. The district closed eight schools last summer and will close six others before fall 2009.

IPS’ enrollment has dropped by about 1,000 students a year for the past five years, as families have moved from the district or sent their children to free public charter schools.

September’s enrollment was 34,086, down 1,200 students from last year. The district has been losing students for decades since its peak enrollment of 108,703 students in 1967.