Things to do this weekend for (mostly) free

If it's outdoors, call ahead. A lot of things are being cancelled due to the rain.

Saturday

NYC Dumpling Festival and eating contest - benefits Food Bank NYC

Kid's Day, Nightmare: Vampires: the very-not-kid-friendly Museum of Vampyric Artifacts hosts an under-10 appropriate day of mysteries, squirt guns and candy ($15)

Halloween Harvest Fair, Staten Island, with colonial crafts and bouncy castle

Afternoon of Ghouls at King Manor - Halloween crafts and activities at the home of our local forgotten founding father, across from the last stop of the E train in Jamaica

High-tech Halloween house - from the students at the CUNY Department of Entertainment Techonology, Brooklyn ($6 adults, $4 students)

Harvest Festival, Bartow-Pell Mansion, Bronx (w/admission)

City of the Future arts event - Architects, builders, and artists help kids built their own new New York

Big Green Halloween Fair, PS 166 (rain date Sunday)

Nature Scavenger Hunt, Van Cortlandt Park

Million Trees planting day, all boroughs

Pumpkin carving workshop, Staten Island ($8)

Early American Crafts and Games, Prospect Park

Karaoke in Brooklyn

Weather permitting, stargazing in Inwood Park. Telescopes and astronomers provided.

Night creature walk in Central Park

Sunday

Glamrock Halloween Harvest Festival, Socrates Sculpture Park, Queens - costume making, face painting, and a dog costume contest

Tai Chi in Fort Tryon Park

Halloween Parade and Pumpkin Sail, Central Park - story telling, costume parade, and a flotilla of decorated pumpkins sailing the Harlem Meer at sunset

Halloween Festival, Fort Totten, Queens - costume contest, hayrides

Zhang Family Band, traditional chinese music at Henry Street, Manhattan

Ghouls and Gourds, Brooklyn Botanic Gardens - costume parade, meet kid's authors, music, performances, mask making and giant puppets (w/admission)

Live Bats, including one with a 6-foot wingspan, at the NY Hall of Science (w/admission). Also at the Hall: Catapult Month demos - science and thing-hurling.

Leaf-peeper walk, Prospect Park

Halloween Haunted House, with hayrides, Queens Farm Museum

Explore Hunter Island, Pelham Bay Park, Bronx

1865 Funeral Recreation, Marble Cemetery tour - Merchant's House Museum (reservations, w/admission. Funeral attire recommended)

All Weekend

It's My Park Day - volunteer to spruce up your local park. Most of the events are on Saturday, but a few are on Sunday. It's a terrific way to meet people in your neighborhood who are self-selected for not being jerks. Plus, clean park. All upside.

Boo at the Zoo, Bronx Zoo - Haunted safari, mask making, hayrides (kids free in animal costumes, adults w/admission)