Applications open this week for the city’s free pre-school programs, and slots for three-year-olds are expanding. The new 3-K classes build on the success of the de Blasio administration’s free, full-day program for four-year-olds. Now, some 3-K teachers want to flag an issue: the 15:2 student-teacher ratio makes it hard to manage classrooms full of young children, some of whom are not fully toilet trained.

New York State requires one teacher and one paraprofessional for 15 kids, which is the ratio required by federal Head Start programs. But many private schools go beyond the state requirement, and 3-K teachers would like New York City to consider changing the rules.

“We want to help these kids, for you to help us, we need training, and we need a third person, badly,” said 3-K teacher Donna Fellowes at a Panel for Educational Policy meeting last fall.

“I dare you to come to my room for 45 minutes and endure nap,” she said. “You’ll have seven toddlers with diarrhea, one throwing up. When my para is in the bathroom with three kids. I’m alone.”

Listen to Jessica Gould's report on WNYC:

The 2019-2020 school year is the first time 3-K has been available in all five boroughs, and, as of September 5, approximately 17,700 students had enrolled in 3-K. Students in 3-K work on letters, numbers, colors, and shapes. But they also practice social skills and learn how to be more independent. And as anyone who hangs out with a toddler knows, independence is always a process, sometimes a struggle, and occasionally a mess.

Martha Foote is director of the tuition-based Park Slope Child Care Collective, which places 17-18 children in classes with four or five teachers. “When you’re working with 3-year-olds, you’re working on so many basic developmental skills: toilet training, learning how to eat independently, and you really need to have more teachers to help them,” she said.

Some leaders at community-based organizations that want to contract with the city’s free 3-K for All program said they’re worried they may have to raise outside money to keep their third teacher.

In a statement, a spokesperson at the Department of Education said the current staffing ratio ensured “safe and healthy” classrooms, and teachers were trained to help children regardless of whether they’re potty trained or not.

A spokesperson for the United Federation of Teachers said it’s working with the department to address teachers’ concerns.

Not all teachers are overwhelmed. At P.S. 173 in Washington Heights, 3-K teacher Meghan Saphire led a cheerful sing-along before sending children off to play.

“It’s going really well,” she said. “The students are really happy. They get to go to gym class, to science class, dance.”

She said children spend most of their days playing which is how they learn best. In these early years “a child learns how to be a student, how to be a friend, and how to be part of a community,” she explained. They also learn how to control their bodies and use the toilet and sink.

Saphire noted that she and her paraprofessional do have to be vigilant, including around potty-training. “We used different tactics like a potty chart,” she said. “So kids who were potty training asking them every 10 minutes and then checking off if they had to go to the potty or not.”

Previously, Saphire taught in a program with three adults per class. She said managing with just two is an adjustment. “It’s doable,” she said. “But having another body in the room would be nice.”

Applications for the city’s 3K program are open through April 24th. Families who live in 3-K districts have priority, but all New York City kids born in 2017 can apply; information at myschools.nyc.