CHICAGO – A Chicago Public Schools math teacher and chess coach who refused to ditch his students for a one-day union strike is also refusing to attend a hearing to expel him from the union for crossing the picket line.

Earle STEM Academy math teacher Joseph Ocol would rather attend chess practice with his team after school June 6 than at a Chicago Teachers Union hearing to expel him from the union, DNAinfo reports.

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He said he skipped the union-organized teachers strike on April 1 because he was busy teaching students.

“I do not wish to be absent because I have always promised the kids that I shall always try to be with them after school even if I do not get paid,” Ocol wrote in a letter explaining why he won’t attend the CTU hearing.

CTU spokeswoman Stephanie Gadlin said the union is giving Ocol an ultimatum: either forfeit the money he earned while his colleagues walked out on students, or he’s out.

“A strike breaker will be given the option to pay a fine equal to the member’s net earnings while working in order to be reinstated, if they so choose,” Gadlin told DNAinfo in an email. “If they choose not to pay the fine they will be expelled from the Union.”

Teachers in Chicago who are not union members must still pay the CTU a “fair share” fee for “collective bargaining services,” whether they want the services or not, but they do not receive the same benefits as full-fledged members.

Union officials have expelled members before, but it’s Ocol’s dedication to his students that makes the CTU’s attack so galling.

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Ocol volunteers his time after school to coach the chess team, and the girls took home the national championship last month, earning the five members of the all-girls team a trip to the White House in June. Ocol is now working to raise money to take all 35 members of the chess team on the trip.

Ocol is appealing the CTU’s efforts to expel him, and said he will only agree to pay the fine for missing the teacher’s strike if the money goes toward helping his students get to D.C., and not in the union’s coffers.

And while Ocol has been working overtime to help his students learn, his union-loving colleagues have sent him “nasty” messages urging him to leave to work at a charter school, DNAinfo reports.

The Illinois Mirror weighed in on Ocol’s predicament in an editorial Tuesday.

“You’re probably just as shocked as I am that an organization led by a woman who recently compared Governor Bruce Rauner to the terrorist group ISIS would go so far as to bully one of their own members for feeling that his first obligation is to his students and not to a private political organization he is ostensibly forced to join,” the op-ed read.

The Mirror also pointed to a feature in Inquirer.net that details not only Ocol’s history of standing up for what’s right – he was a key witness in a government corruption case in his native Philippines before he was forced to start over in the United States – Ocol also built the chess program at Marshall Metropolitan High School from scratch after a student was shot and killed by gangs after school in 2005.

“The original idea was to keep kids safe in school when it’s most dangerous,” he told Inquirer.net, adding that most violence occurs between 3 and 6 p.m. “We wanted to hold them in school for a while and chess was one alternative.”

The 2014 article went on to detail how Ocol’s chess program continued to grow, and now helps instill a purpose and sense of pride in students, who are now taking home national championships.

According to The Inquirer:

The chess club started with just a handful of interested students.  Ocol sometimes dipped into his pocket to buy pizza and snacks to woo more members.  In 2006, Ocol decided to expand his chess program to include not only high school students, but grade school and kindergarten pupils as well. He invited  kids from nearby Faraday Elementary School.  From eight students in 2005, the chess club membership from the two schools grew to more than 100 in 2010.

Ocol included in the chess program a unique mentoring scheme, where students became mentors of other students; high school kids helped elementary school kids, or in some cases, elementary pupils, who were  quite advanced in their knowledge of chess, mentored high school students.

“This mentoring program cultivates self-esteem, self-confidence and self-reflection among kids.  They become masters of their skills when they start teaching those skills to fellow students,” Ocol said.