In Kelly Stevens' kindergarten classroom, each day begins with circle time for what sounds like a menu of lesson options.

Students — or "friends" as Stevens calls them — can read at the green table, they can build boats or make things out of clay, among other options.

Students Marco Carias Castellanos and Holden Free chose a writing activity today. But there's no worksheet in front of them. Instead, they're standing in front of wolf statues they made out of blocks and their assignment is to write labels for body parts.

"I'm making an ear!" says Marco. "Ear! E! E! E!" adds Holden.

Play-based activities like this one at Curtis Guild School are part of a new curriculum that Boston has been rolling out over the last five years. It's a deliberate shift away from the " kindergarten as the new first grade," way of thinking that's become common in early childhood circles.

The thinking is that play, student-led activities and lots of choices work just as well for older kids.

"I used to be very regimented and structured," explains Stevens. "I didn't like the blocks because it was messy and it was loud."

Stevens has been with the Boston public schools for almost 20 years. For most of her career, she was in the front of the classroom, while the students watched and learned in desks and seats. Now, her room is filled with play stations; there's a jungle corner, a painting area, even a mini kitchen.

"Instead of this sort of top-down approach where the teachers have the knowledge, you have to let the kids explore," says Jason Sachs, the district's director of early childhood education.

Boston's approach allows teachers to juggle the many needs of young students with different skill sets, Sachs explains.

That's a big challenge for teachers. Boston has invested a lot in preschool over the last decade but there isn't room for all 4-year-olds. The city still has a wait list of about 1,000 kids this year.

That means Boston's kindergartens are a mix of students — some who have that extra year, and some who don't.

For students who did manage to get a spot in preschool, "the curriculum can stretch and you can grow with it," says Sachs, rather than get caught in a holding pattern while kids who didn't go to preschool catch up.

For those who missed out on preschool, "there still needs to be room for you to navigate and be a contributor."

In the new curriculum, he adds, there's room for both types of students.

This mix of students is a factor in what many researchers call the fade-out effect. While research backs up the benefits of high-quality preschool, there's also data suggesting that kids who went to preschool perform about the same on standardized tests as those who didn't by the time they hit third grade.

The curriculum changes Boston is embracing, are happening across the country, says Lori Connors-Tadros a senior project director at the National Institute for Early Education Research. She helps states improve their early learning policies.

"We are in the middle of this sea change," Connors-Tadros says. "Now, [states and cities] are investing in specific guidelines and practices," for high quality kindergarten and grades 1-3.

So, is all of this effort actually making a difference? That's what a group of researchers at the University of Michigan, Harvard and MDRC are investigating in Boston.

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