Four-year-old Jake Basseches went to the Harvard Museum of Natural History yesterday dressed as Superman. The son of Joshua P. Basseches, the museum's executive director, Jake was just one of the many children who put off their trick or treating for a few hours to discover the wonders of the museum at its Halloween Open House.

For the second year, the museum was festooned with cobwebs, skeletons and orange and black streamers, attracting over 300 people to the Halloween festivities.

"We're always looking for ways to bring more people to the museum," Basseches said. "This is a great way to do it that's both fun and educational."

Parents led their costumed children through the winding rooms of exhibits, all filled with hands on activities for all to participate in.

More than 25 volunteers were scattered throughout the museum, providing answers to questions about different exhibits and helping children to make crafts.

Nancy A. Murphy, the museum's education coordinator, had a large part in organizing the activities.

"It took a lot of planning," Murphy said. "But it's definitely worth it if the kids have fun and we can show them that museums don't have to be stuffy."

Children were first greeted with a "Creepy Critters" exhibit, featuring scorpions, millipedes and tarantulas, some of which the visitors could hold.

Andrew S. Majewski, a volunteer who helped run the exhibit, said he was intrigued by the influence parents had on their children at the exhibit.

"The kids reacted as their parents reacted," Majewski said. "If the parents showed interest and were willing to hold the insects and spiders, so were the children. If the parents backed away, so did the kids."

The other rooms featured hands-on crafts, such as paper aliens at the meteorite exhibit and beaded jewelry near the gem and birthstone display case.

Flashlight and glow-in-the-dark tours added mystery to the shark and prehistoric mammal galleries.

The event was expanded from last year, with the adjoining Peabody Museum of Archeology and Ethnology providing a "Day of the Dead" exhibit in its Central American gallery.

Harvard's Ballet Folklorico dance troupe performed at the open house, introducing children to traditional music and dance from Mexico in order to show them the different ways that Halloween is celebrated.

Kyle B. Roberts, assistant to the executive director of the museum, said that the event had fulfilled its purpose of educating children in a fun setting.

"It's great to follow the kids," said Roberts, "and see the looks of discovery on their faces when they see a whale or meteorite for the first time."

Museum officials said they hope exposure to the museum world will provide a stimulus to children to want to learn more.

"We had a good turnout," Basseches said. "Hopefully, the children will want to come back in the future just to see the museum."