As Monday approached, social media in Central lit up with parents making the last-minute decision to have their kids skip the first day of Common Core standardized tests.

The number of opt-outs stood at about 90 Thursday, grew to 120 by Sunday, and on test day Monday reached 153, Central Schools Superintendent Michael Faulk said.

“It just grew and grew until we had what we had this morning,” Faulk said.

Those students represent almost 8 percent of the more than 2,000 third- to eighth-graders in Central who were supposed to take the new tests known as PARCC, which is short for Partnership for Assessment of Readiness for College and Careers. Only two other school districts, Jackson and Calcasieu parishes, had higher opt-out rates, 13 percent and 12 percent, respectively.

Those districts are outliers. Statewide about 1 percent of students opted out, and many school districts reported full participation, including East Baton Rouge, Pointe Coupee, St. Helena and West Feliciana parishes.

The next highest opt-out rate in the Baton Rouge area is West Baton Rouge Parish, where about 4 percent of the students in that school district declined to take the tests Monday.

Faulk said he sent out information to Central families in advance of testing to try to dispel myths and persuade families to change their minds, and a few did, but they were outnumbered by new opt-outs. He said the families that early on said they were opting out had concerns about Common Core standards, and the PARCC test itself, but the late opt-outs were infected by panic, which he said was spread largely through Facebook.

“I bet many of them couldn’t even tell you why they’re opting out,” he said.

Faulk said he’s worried that more Central students will opt out still, either later this week, or during the second round of PARCC testing, scheduled to occur in May. And because many of the students opting out are ones who have scored above average on past standardized tests, and because Central is a small school district, Faulk said, he’s worried that Central’s scores — the district was ranked third in the state last year academically — will take a nosedive.

He said he has scheduled a face-to-face meeting with State Superintendent John White two weeks from now to press again for some relief, otherwise the test results for Central public schools will be erroneous.

“When you have so many students not taking the tests, how is that a reliable indicator of what the teachers and staff have done at that school?” Faulk asked.

Follow Charles Lussier on Twitter, @Charles_Lussier.