Some teachers plan to picket May 14 school board meeting.

Teachers union says nearby suburban teachers are paid 20% more on average.

Average teacher salary in Detroit is $57,997, according to state data.

Some Detroit teachers plan to protest a new school calendar that adds five workdays without increasing their pay.

"The district already has terrible trouble filling its numerous vacancies, because of the low pay and difficult nature of our work," said teacher Ben Royal, a member of Equal Opportunity Now/By Any Means Necessary, a caucus within the Detroit Federation of Teachers, which takes a more militant stand. "This causes terrible overcrowding in many, many classrooms, which means students don't get the attention they deserve, and student achievement declines."

Royal said many teachers are angry and plan to picket the May 14 school board meeting. If that doesn't work, some have already begun discussing additional ways to protest.

"There are other options, that teachers are prepared to do, like reorganize the sick-outs from a few years ago," he said.

In 2016, hundreds of Detroit teachers called in sick on the same days to protest what they said were unsafe building conditions, low wages and other problems in the district. The district considered the sick-outs an illegal strike and sued the organizers. A federal judge later ruled on behalf of the teachers saying their protest was protected under the First Amendment.

The Detroit Public Schools Community District board earlier this month approved the calendar for the 2019-20 school year. Among the changes are plans to seek a state waiver to begin school before Labor Day and to reduce the late winter break in February from a full week to two days.

Superintendent Nikolai Vitti said teachers were included in creating the calendar and their union approved it.

"DFT approved the calendar, along with all of our other employee unions, as did the board," Vitti said in a statement. "We plan to address misconceptions with the calendar with teachers, such as snow days and PD days. The calendar was created with several stakeholders, including students and parents.‎"

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Union President Terrence Martin denied union approval of the calendar.

"The reality is that our local has neither agreed to nor signed off on the academic calendar," Martin said in a statement. “Our Detroit Federation of Teachers (DFT) members have spoken loud and clear in opposition to the new and proposed 2019-2020 Detroit Public Schools Community District (DPSCD) academic calendar. We are very clear that the calendar not only affects students and parents but also our dedicated and hard-working DFT members."

Royal insists the new calendar was forced on teachers.

"This was not one that any members had seen prior to it being adopted," Royal said.

At a union meeting last week, teachers present unanimously approved a resolution calling on the district to rescind the calendar and reinstate the old one. It's not clear how many teachers attended that meeting.

The calendar dispute comes amid contract negotiations between the district and the union. Under the current contract, which expires in June 2020, a teacher with a bachelor's degree has a starting salary of about $35,700 with pay raises added as the teacher gains experience.

In the 2017-18 school year, the average teacher salary in Detroit was $57,997, ranking the district 229th out of Michigan's more than 500 districts and charter schools, according to data compiled by the Michigan Department of Education.

Among Wayne County school districts, only the Harper Woods and South Redford Schools have lower average teacher salaries than Detroit, according to the data.

Vitti has said he wants to institute some type of merit pay to reward teachers whose classes excel, a move the union has long opposed.

Royal said that teachers in nearby suburban districts earn about 20% more, on average, than Detroit teachers and the move to add school days only increases the disparity. He also said that the current contract precludes pay cuts.

"Allowing the current calendar to go forward without a concurrent salary increase at each step would constitute a violation of this provision by reducing our daily rate of pay," the union's resolution says.

Contact John Wisely: 313-222-6825 or jwisely@freepress.com. On Twitter @freepress.com