(CBS) — The Chicago Teachers Union says Wednesday its delegates voted overwhelmingly in favor of a one-day strike on April 1.

CTU President Karen Lewis said 486 delegates voted in favor to 124 voting against it. Union members will be asked to show up at their schools at 6:30 a.m. and start picketing outside their schools.

“The reality is that people are very, very upset and want to do something,” Lewis said.

Teachers have been told that CPS will consider the action an ‘illegal strike” and teachers will not be paid.

Lewis calls it an unfair labor practice strike. She says it’s legal and that the short strike is not about the contract, but about conditions, cuts and a need for Springfield funding help and a state budget.

CPS disagrees, saying teachers can’t strike until after fact-finding is completed in mid-May. They say they will take the teachers to court.

“We’re particularly disappointed that the CTU leadership has given Governor Rauner more ammunition in his misguided attempt to bankrupt and take over Chicago Public Schools,” said CPS CEO Forrest Claypool in a statement.

Lewis doesn’t see it that way.

“We will not be cowed by Governor Rauner and his crazy agenda because you know what I think about that and you know what most people think about it,” Lewis said.

Claypool says CPS will outline contingency plans for parents on April 1.

Earlier Wednesday, Mayor Rahm Emanuel said he is opposed to the idea, saying union leaders should be at the bargaining table, and teachers should be in the classroom.