Waterbury schools will begin notifying parents starting next week, some students would have to be transferred.
Over the past two years, more than 600 students have been added to the Waterbury School District.
"It disrupts daily lives and households and I feel for the other parents that are going to be going through this as well," said Amy Milo of Waterbury.
In just three days, Milo said her 5-year-old daughter will be forced out of her current school, Chase Elementary.
"She's been in there for a couple of months now, there hasn't been anything brought up about it and then all of a sudden I get the letter," Milo said.
Milo said she got this letter Wednesday from the Waterbury School District, which told her that as of next week her kindergarten-age daughter would be transferred several miles away to Hopeville Elementary.
"They gave us such short notice, I don't know what to do about daycare," Milo said. "I had something setup with the boys and girls club but they don't work with the school she's going to."
The school district told Eyewitness News it had no choice.
"Our teachers union contract requires a certain class size limit," said Waterbury School District's Chief Operating Officer Paul Guidone.
Waterbury schools said its teacher's contract mandates kindergarten classes can't have more than 20 kids. Last month, the district began verifying the size of each class and found in about 30 cases, the classes were too big.
"Unfortunately, especially at the elementary level, there are not that very many seats available because of our contractual limits," Guidone said.
"I wouldn't have been upset if we had a month's notice, I had time to figure out day care," Milo said.
The district said it waited until now because students tend to transfer schools or move out of the district during the first month of school.
"I'm definitely going to appeal it," Milo said. "My worry is my daughter's well being. I don't think it is going to be good for her."
The district said it is allowing parents to appeal.
In some cases, students next year may be allowed to switch back to their original school because older classes are allowed to be larger.
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