Two generations of children have crawled through the dim tunnels of the “anthill” since the Minnesota Children’s Museum opened in downtown St. Paul in 1995. But there won’t be a third.

Several well-loved and well-worn original exhibits are closing to make way for eight new indoor exhibits as part of the museum’s $30 million expansion.

World Works closed this week. The anthill in Earth Works and the toddler haven of Habitot close Aug. 24.

So, head over to the new skyway entrance, buy a ticket at the new second-floor box office, and see if you can still squeeze through that tunnel.

The first new permanent exhibit, Forces at Play, opens Aug. 27 in ground-floor space previously occupied by museum offices, looking out big windows onto West Seventh Street. Kids will be able to explore air and water pressure by building an air-powered ping-pong launcher or turning a crank that spits foam into the wacky car wash.

The museum will close entirely in November for construction and will reopen in April with a four-story glass box addition and climbing structure, maker spaces, a bigger toddler area and even more places to play.

IF YOU GO

Hours: 9 a.m.-8 p.m. Friday-Saturday and 9 a.m.-5 p.m. Sunday-Thursday

Admission: $9.95 (free for children younger than 1)

Contact: 651-225-6000 or mcm.org