Ohio legislators are on the verge of falling into a trap on education funding that would stick taxpayers with future tax hikes to fund big pay for teachers’ unions.

As they consider the next two-year budget, lawmakers must wrangle with education funding. Expanding school choice options has been a priority in recent years, and a worthy one at that. It has never been more clear that parents need control when it comes to choosing where and how their children are educated.

As legislators aim at a new school funding formula that will serve expanding school choice, they must take care that the formula does not lock in more spending growth than Ohio taxpayers can afford. That would lead to tax hikes.

Unfortunately, the proposal being advanced by the Ohio House of Representatives would do just that. Worse, it would lock in unaffordable spending levels by giving teachers unions power to drive up costs for the state.

House Bill 1 is the school funding bill, now part of the House’s biennial budget, HB 110. The legislation would increase school aid from the state, for traditional school districts it would go up by nearly 24% compared to current law.

That is a significant amount of spending and worth a closer look by taxpayers even if it can be paid for by naturally rising revenues or changes in spending priorities. But these numbers don’t even represent the full cost of HB 1. They only reflect what the cost of HB 1 might have been in 2018, without additional funding for economically disadvantage children.

You may have noticed it is 2021, not 2018, presumably Ohio representatives also are aware of this. So why are they using old, 2018 numbers for district costs and salaries to inform a formula that will go into effect in 2022?

Whatever the reason, an already significant increase in aid spending (24% for traditional districts) is actually a lowball figure. It’s based on old school district costs. It also does not take into account ongoing analysis of how to aid economically disadvantaged students, which will add more guaranteed spending to state aid.

In short, old data on school district spending, and outstanding recommendations on additional aid for students from low-income families will significantly drive up the projected cost of the new school aid formula.

Taxpayers don’t know the true cost, but if this version of the funding formula passes, they will be on the hook for whatever that cost ends up being. If the state tries to go under the formula, school districts will be able to sue to get money to fill any such gap. Since their costs and salaries are under their control and feedback into the formula to demand more aid, districts can drive up costs for state taxpayers.

Legislators who support this version of the school aid formula are locking Ohio taxpayers into paying far higher aid costs than they do today, and empowering teachers unions to keep driving those costs up. On top of that, future demands for additional school funding will be made on top of the ever-rising baseline guaranteed by the formula. Before deciding on a final formula, legislators should address these concerns, and be clear on what the state will actually end up spending.