Charter school supporters delivered a petition to Governor Charlie Baker on Tuesday containing 25,000 signatures asking the Legislature to lift the cap on the independently run, publicly funded schools.
Baker, who has filed a bill that would allow 12 new or expanded charter schools statewide each year, used the State House event to again ask lawmakers to raise limits on charter schools before the current legislative session ends in July.
He recalled the passage, more than two decades ago, of state legislation "giving these experimental schools a chance to see what they can do in educating kids."
"It's not an experiment anymore. It's not a demonstration. It's not a what-if," he said. "After 20 years, we have overwhelming evidence . . . of kids, parents, families who have found what they were looking for in the charter school movement here in the Commonwealth of Mass."
The charter school cap is one of the most divisive issues facing lawmakers.
Many Massachusetts charter schools have above-average test scores, but critics say such results are skewed because charter schools often take on fewer children with special needs than district schools and sometimes have strict discipline policies that drive out harder-to-reach students.
Charter school proponents deny claims that they use discipline to cherry-pick students and say they have taken on increasing numbers of special education students, though charter schools usually do not offer programming for students with the most profound needs.
Boston resident Dawn Foye said at the State House that her son, who has an individualized education program, has been thriving at KIPP Academy but will be unable to go past eighth grade at KIPP because the charter cap prevents the school from opening a high school.
"Unless the cap is lifted, Brandon's going to have to leave the school that he loves, that I love," she said. "And that's just wrong."
Senate President Stanley C. Rosenberg has expressed skepticism about the likelihood of the Legislature lifting the charter school cap. If lawmakers do not act, a referendum to lift the cap could appear on the November ballot.
A separate lawsuit seeking to lift the cap was filed in Suffolk Superior Court in September, but state Attorney General Maura Healey has sought to have the suit dismissed.
Baker accepted the petition from Foye and about 30 other parents wearing shirts that said, "Great Schools Now," a slogan used by Great Schools Massachusetts, a business-backed coalition that may spend up to $18 million to fight the charter school cap, the Globe has reported.
The group stood before a banner saying, "37,000 kids are waiting. It's time to lift the cap."
Baker also referenced that number, speaking of the "37,000 families on waiting lists." But state Auditor Suzanne Bump has disputed that number, saying data collection methods used by the state Department of Elementary and Secondary Education in compiling the list are unreliable.
Jeremy C. Fox can be reached at jeremy.fox@globe.com. Follow him on Twitter @jeremycfox.