Editor’s note: The annual Mosaic Journalism Workshop for Bay Area high school students is a two-week intensive course in journalism. Based at San Jose State University’s Spartan Daily newsroom, Mosaic students report and photograph real stories under the guidance of professional journalists.

Two days before the school year ended, teacher Aaron Calvert took his Summit Denali charter school students on a walking field trip to downtown Sunnyvale to explore opportunities for the future: internships, summer jobs and independent study projects.

Later that day, a student asked if Calvert was returning for the following school year. He responded, “Yes I am, unless I win the lottery.”

At the end of the last day of school, Calvert found out he will not be returning, but not because he won a lottery. Instead, his bosses terminated his contract, after he had already signed on for the following school year.

Two other staff members at Summit Denali — physics teacher Andrew Stevenson and English teacher Evelyn DeFelice — were also terminated despite already having been rehired for the fall. All three teachers said they did not get a detailed explanation for why they were let go beyond “business reasons.”

In the days that followed, their colleagues launched a public petition to reinstate the terminated teachers. Diane Tavenner, CEO and co-founder of Summit Public Schools, declined to go into detail about the situation but said they were student oriented.

“At Summit, business reasons are student reasons,” Tavenner posted on the online petition. “While we cannot discuss specific reasons for personnel decisions out of respect for the employees’ privacy, we can assure you that the question of what is best for students is the value that has guided our actions for 16 years.”

All three teachers were prominent supporters of Unite Summit, a union campaign launched earlier this year, in hopes to gain more say in the quality of their careers and students’ education.

Summit is among the latest charter schools in California to unionize, joining a growing trend in a sector that for years did not have organized labor.

Calvert and DeFelice were part of the organizing committee and Stevenson was elected as a bargaining team representative. Unite Summit has filed an unfair labor practice grievance with the state Public Employment Relations Board over their terminations.

Frank Wells, a spokesman for the California Teacher Association that backed the unionizing effort, said there is nothing in the law that prevents charter school teachers from being fired without certain notice or explanation, and said a union contract could serve as protection from that.

One of Unite Summit’s top priorities is improving mental health services for students.

When he initially joined Summit Public Schools, Keith Brown was a mentor and teacher at Summit Denali. At each of the Summit schools, every student is placed into a small group and assigned to a mentor.

Brown said he felt he was not adequately trained to properly react to the mental health issues that arose in his mentor group. Calvert said because mentors are expected to act as therapists without proper training, it can cause emotional burnout, affecting teacher retention.

“There are times when Summit treats its faculty like fossil fuels: It just burns them up and goes looking for more,” Brown said. “I believe the mentor system is wonderful and it needs to be protected.”

Summit Academic Chief Caitlyn Herman said it is not a teacher’s responsibility to provide professional-level mental health support to students.

“None of our teachers are expected to be experts on mental health. That is not their role,” Herman said.

In an interview with Mosaic, Tavenner said that the mentorship system is meant to primarily address the college admissions process and students’ post-high school future.

She said Summit’s multi-tier support system where student support is a collective responsibility of administrators and faculty is more beneficial than the conventional system of having full-time counselors. Chief of Staff Kelly Garcia said there is also a comprehensive teacher support system, where they rely on the chain of command for guidance.

Tavenner also acknowledged a union complaint about inconsistency of leadership meetings across different school sites, saying the administration has begun planning how to improve communication across all Summit campuses.

Unite Summit in January submitted a petition to PERB showing over 75% of Summit educators were in favor of unionizing. However, the Summit administration is challenging which employees are eligible for representation, a dispute currently being reviewed by PERB.

Some teachers had transparency concerns about the union campaign. Mary Beth Thompson, a history teacher at Summit Prep in Redwood City, said some teachers didn’t know a unionizing effort was underway until the result of the petition was announced. Thompson contends some teachers signed the petition not knowing their signatures counted as votes to unionize.

Thompson believes a union is not necessary to improve the Summit organization. She said retention has been addressed in part by administrators implementing a teacher-proposed stipend policy that pays more for staying at Summit longer. She said she and her colleagues considered staying longer at Summit due to the bonuses.

Thompson also opposes Unite Summit’s affiliation with the CTA, based on the statewide union’s support for legislation that she believes threatens charter schools’ viability in California.

There are several proposed bills in the state Legislature that if passed would expand the allowable reasons to reject a charter school’s application for renewal, make the appeals process for charters more difficult, and increase public oversight.

Supporters of the bills believe they would institute much-needed accountability for charter schools while critics say the bills will inhibit the expansion of charter schools or force them to close.

Summit Prep AP U.S. history teacher Chris Kelly said he believes the link between Unite Summit and CTA will “add another layer of bureaucracy teachers will have to go through” from entities that lack expertise about charter schools.

Wells said such a concern is overstated.

“They would have a collective bargaining agreement, so I am not sure why they would think that being affiliated with CTA would impede their ability to meet student needs,” he said.

DeFelice said a union would represent a “culture change” because the teachers who directly interact with students would be able to voice what’s best for them.

“The idea is to work with administration,” she said, “and not against them.”