Parents at a D.C. elementary school are vowing to fight for an extra $10 million to fund a renovation project, saying the city deprived them of much-needed money in the middle of the process.

Renovation plans for Murch Elementary School in Van Ness — a prosperous neighborhood in upper Northwest — have been in the pipeline for years, and the city had allocated $68 million toward it.

During the past year, officials presented parents with detailed plans for the renovated school grounds, including an underground parking garage, extensive playgrounds and a large cafeteria.

But D.C. Public Schools and the city’s Department of General Services recently said that they miscalculated and that the plans would cost about $88 million — not $68 million — and that the school system is asking Mayor Muriel E. Bowser (D) for an additional $10 million to meet in the middle.

The parents say the city should increase its budget to the full $88 million instead of scaling down the renovation plans.

“It’s like Charlie Brown in football. You keep going to kick the football, and they keep moving the football,” Maggie Gumbinner, co-president of the Murch Home and School Association, said at a meeting Wednesday night. “But we’ve got to keep kicking.”

Even with the additional $10 million to boost the project to $78 million, the school would need to use a large chunk of that to pay for students to move to the University of the District of Columbia campus for two years while the facility is built. The new budget would require the school to downsize its plan, including nixing the underground parking garage and making a planned media room smaller.

Still, at $78 million, the Murch project would be one of the two best-funded renovations out of the 18 city elementary schools that are under renovation or slated for work.

Lafayette Elementary School — a mile away from Murch in the Chevy Chase neighborhood — is undergoing a $78 million renovation project. Lafayette and Murch are among the District’s highest-performing and largest elementary schools.

Murch, which is 80 years old, has never been fully modernized, and parents say the facilities are too small and outdated to accommodate its enrollment of more than 600. Some classes are taught in trailers on school grounds, and parents complain that students have to eat lunch in classrooms, which means mice are not an uncommon site on campus.

“I’ll be the first to admit that when coming up with the budget, there were assumptions that were not correct,” Patrick Davis, the city school system’s coordinator for facilities initiatives, said at the parents’ meeting.

Construction at Murch is scheduled to start this summer, and city officials and contractors have quickly worked to revise the renovation plans to meet the new budget.

Despite the rushed timeline for the proposed plan, which would require the approval of the District’s zoning board, officials say the renovations should still be completed in time for the start of the 2018-2019 school year.

Under the new proposal, there will be no underground components, which had been the most expensive aspects of the pricier plan. But parents say that because the Murch campus is smaller than most elementary schools, the underground space is necessary.

“It’s inappropriate to put in aboveground parking and take away our kids’ playground space,” said Marsha Goodman-Wood, a parent of a 4-year-old and two graduates of the elementary school. “This is a no-go for us. We are not going to compromise our kids’ education because somehow in this process you made a budgeting error.”

When the construction is complete, there will be no trailers, and Davis assured parents that all students will be able to eat lunch in a cafeteria. There will be ground-level parking, with a gymnasium above it.

D.C. Public Schools spokeswoman Michelle Lerner wrote in an email that school officials “are confident that we will be able to deliver a great building for the Murch community.”

Ron Eckstein, a parent and member of Murch’s School Improvement Team, said he realizes that the renovation project has a large budget, but he also believes that the plans barely meet the basic needs of the school and that there isn’t room for cutting. Other parents at Wednesday’s meeting said that for years, they fought hard to persuade the city to allocate the money it promised and want to ensure that the full project is realized.

“We rallied once. Why aren’t we re-rallying for another $10 million?” parent Lesley Rich said. “It’s ridiculous.”

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