For the third year in a row, Portland voters will be asked to approve a school budget that cuts spending and reduces staff. But this budget has the potential for controversy because it calls for something the others did not — a 3 percent tax increase.

The reason is not out-of-control spending but the loss of federal funds that came from the economic stimulus program. School officials have long warned that the program’s expiration would result in Portland’s worst budget shock of the recession, and even when they had the money, they spent prudently, cutting positions and finding efficiencies.

But the loss of $4 million in federal funds, even when it’s softened by last year’s “jobs bill” subsidy, will increase the amount of money to be raised by taxes, even though overall spending is down.

Parents of kids in the schools know the result of several years of budget cuts. Deferred maintenance in several buildings is leading to obvious problems.

The schools have not kept up with technological innovations. And teachers are handling more students in the classroom at the elementary levels and more sections in high schools.

For voters who don’t have kids in the schools, the question remains:

Is it really necessary to raise taxes now, in the aftermath of a recession, while growth is still unstable and many families struggle to pay their bills?

They should know that there are cuts in this budget, with more than 50 positions eliminated. There is a creative teacher contract with more than $1 million worth of wage concessions.

But there is still a shortfall and it requires a 3 percent tax increase, asking $2 million more from city property owners.

The whole community benefits from having a strong school system. Portland residents have shown in the past that they are willing to pay what it takes to make the system strong, despite the unique educational challenges the city faces.

No one likes a tax increase, but on May 10 Portland voters should do what they have done before and support the school budget.