They're picketing outside La Entrada Middle School and Las Lomitas Elementary School.
UPDATE: Menlo Park teachers reach tentative agreement with school district, strike ends
Teachers say they've been working without a contract for more than a year and a half.
And with the rising cost of health care and rent, many say teachers they can no longer afford to live in the district.
"We currently do not have full benefits, and we are one of the lowest paid of 'comparables' in our district for a starting salary, and we are asking management for a fair compensation," said Jennifer Montalvo, co-president of the Las Lomitas Education Association.
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Montalvo serves as a school counselor, with more than 20 years of experience in the district.
"We are at the top of the salary schedule. The only raise we will get is through a negotiation because we are at the top," she said. "And with the rising cost of healthcare and the premiums, the increases in my paycheck is smaller today, after all these years, than it was a few years ago and that keeps happening."
The district says it offered a 5% salary increase plus almost $2,000 in additional healthcare benefits per employee back in May, claiming this would put the district at or near the top of the pay scale compared to neighboring districts.
It says it can't accommodate a requested 10% salary increase without putting the district in the red by several million dollars over the next few years.
But the union says it was left high and dry at the bargaining table until Tuesday night.
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"After sitting down at the table, they sent us off to caucus and indicated that they would call us back to the table when they are ready," said Daniella Lefer, co-president of the Las Lomitas Education Association. "Two hours went by, and we went to go and check the room. It was dark. Their cars were gone. They never told us they left."
Despite the strike, school is still in session.
But Debra Fisher decided her daughter Kathryn's time was better spent helping her teachers.
"I feel so strongly that we should have never been put in this situation to begin with," Fisher said.
She's spoken out at several past school board meetings, questioning where the money went.
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"It's hard to understand where the money went. That's kind of what they're chanting, because we're one of the wealthiest districts, and so I've read some of the numbers and just don't understand where all the funds are," she said.
The schools are open, but we're told many students are being divided into larger class sizes or kept in the gym.
All afterschool activities are canceled.
The district is also limiting transportation and special education services.