The governor had been outspoken in his opposition to the tax-cut bill that he said would drain as much as $620 million from the state budget.
Appearing before a group of northwest Missouri school boards earlier this week, Nixon said funding for education would take the brunt of the hit.
Republicans and democrats disagree on what the veto will do to public schools.
Republicans say spurred economic growth will lead to more dollars for schools. Democrats say there will be big cuts to education, as much as $3.5 million in the case of St. Joseph schools.
With the jockeying in Jefferson City, local officials say it's hard to know what to think.
"We kind of hate to bet on the next card," said Steve Huff with the St. Joseph School District. "We have some confidence in the School Board Association and the governor's folks that it would probably be a little more detrimental than good.
With the governor's veto, SB-509 will be sent back to the state legislature where an override attempt is possible.