From new exhibits to holiday festivities, autumn in New York is a wonderland for families with children.

This fall, even perennial favorites have something new to offer. Tomorrow, the Children’s Museum of Manhattan (212 W. 83rd St., between Amsterdam Avenue and Broadway, 212-721-1234) opens its new “PlayWorks” exhibit. Designed around the idea that young children learn by playing, the exhibit — which includes an alphabet-centric alligator and a mini–New York dubbed the “Little Apple” — offers a unique play-based learning environment for children up to age 4.

Across the river, the Brooklyn Children’s Museum (145 Brooklyn Avenue at St.Marks Avenue, 718-735-4400) opens its “Berenstain Bears” exhibit October 7. From the familiar old tree-house door to the Bear County School classroom, children will be able to check out the world of the beloved bear family. Elsewhere in the borough, the Jewish Children’s Museum (792 Eastern Parkway, at Kingston Avenue, 718-467-0600) will open an entire floor of exhibits this fall. Titled “Exploring Jewish History,” the floor includes sections called “matriarchs and patriarchs,” “temple and tabernacle,” and “the land of Israel.”

Many ongoing children’s series have started up again this fall. One relatively new favorite is Big Movies for Little Kids, a film series for children ages 2 and up. It takes place every other Monday (excluding holidays) at 4 p.m.at Cobble Hill Cinemas on Court Street. Fall films include “A Hard Day’s Night” (September 18), “Kirikou and the Sorceress” (October 2), and “Spirit: Stallion of the Cimarron” (November 13). Admission is $6 a person. Check out bigmoviesforlittlekids.blogspot.com for more information.

As if the ferry ride wouldn’t be exciting enough, at Staten Island’s Historic Richmond Town (441 Clarke Ave. at St. Patrick’s Place, 718-351-1611) you can take the children to see the city’s oldest continually farmed site. The October Weekends program features self-guided tours, hayrides, children’s crafts, and pumpkins for picking and purchasing. October 15 is “Old Home Day,” where children can see how things were done in Colonial days. Blacksmith and tinsmiths will be at work, as will chair-caners, lacemakers, quilters, and cooks making bread and soups. Children will get a chance to spin their own wool and sample apple cider pressed before their eyes.Admission is $7 for adults, $6 for seniors and $5 for students and children 5-17.

Fall is filled with holidays designed for family fun. The Feast of St. Francis (October 1), otherwise known as the Blessing of the Animals, brings together some 5,000 people and their pets in a celebration of creation at the magnificent Cathedral of St. John the Divine (1047 Amsterdam Ave., between 111th and 112th streets). A fun event for children and their furry friends, the service includes a special Mass and a procession of animals to the altar. Afterward there is a fair on the lawn outside, with a blessing of pets by the cathedral clergy, along with stalls selling crafts and food.

During Columbus Day weekend (October 7–9),New York Public Scavenger Hunts hosts its Secrets of Central Park Scavenger hunt, where children and adults work together to explore the park below 72nd Street. To score points, they’ll have to do things like stick their tongues out at a rude animal and learn the motto of a hidden eagle. Recommended for ages 7 and up. (Check www.watsonadventures.com for more information).

With fall comes the greatest children’s holiday of them all: Halloween. There is arguably no better place for children — and their parents — to celebrate than New York City, where parades and festivities abound. On October 22–23 and 28–29, the Bronx Zoo (Fordham Road at Bronx River Parkway, 718-367-1010, www.bronxzoo.com) hosts its annual Boo at the Zoo event. The weekends’ activities include magic shows, spooky stories, music, costume parades, a hay maze, and pumpkin painting. The zoo’s creepiest critters will be on hand.

On Saturday, October 28, Brooklyn’s Prospect Park (www.prospectpark.org) will host its annual Halloween Walk and Carnival featuring Halloween-themed events including games, music, hayrides, a Creepy Crawly Fun session on spiders, and a “haunted carousel” in which the park’s vintage merry-go-round will be decked out for the holiday.The Skyscraper Museum (39 Battery Place at West street, 212-945-6324, www.skyscraper.org) puts on a Halloween costume workshop at which children over age 4 can make costumes based on their favorite skyscrapers.

The New York Aquarium (West 8th Street at Surf Avenue, Brooklyn, 718-265-3474) offers Sea Monsters Weekend on October 28–29. The New York Botanical Garden (Bronx River Parkway at Fordham Road, 718-817-8700, www.nybg.org hosts Goblin Fun, a festival of holiday activities inspired by the bounty of the garden. Activities include leaf rubbings, pumpkin designing, and spider plant potting.

On Halloween night, nothing beats the Greenwich Village Halloween Parade (7 p.m., Sixth Avenue, between Spring and 23rd streets).Anyone in costume is invited to join the parade.