Saturday at 4, They Might Be Giants perform a free concert at the Prospect Park Bandshell for a $3 donation, as part of Celebrate Brooklyn. Info, here.

Also on Saturday, the Kris Waldherr Studio-Gallery (this woman is amazing), is hosting an opening for the show, Brooklyn: Through a Child’s Eyes,” featuring the illustrations of 21 kids ages 3 to 9, who created the work in a single afternoon recently. There’s a book, too. Noon to 3, 1501 Newkirk Ave. (entrance on Marlborough Road, around the corner from subway station), 347-406-5811.

If you’re hitting the road or the skies this summer, plan now for a bon voyage at Flight 001′s sample sale Saturday and Sunday at their Smith St. location (132 Smith St.). The travel store, whose online product menu includes everything from aerotherapy to “jet comfort,”  is celebrating Bastille Day and selling “one of a kind” samples, cds and an assortment of bags. There’s also a packing-themed raffle.

Or brings the kids to the Brooklyn Children’s Museum (145 Brooklyn Ave. at St. Marks Ave.) tonight at 5 for the first of the Target Free Friday Family Jams. Ugandan music and dance will be featured tonight, with some film shorts and African Pearl Troupe leading a drum session (bring your own drum to join in), 5-7:30; admission free after 5. Then come back for the museum’s Sportacular Weekend (Saturday and Sunday), where the family can learn about world sports, fitness and nutrition and the athletes of the animal world (maybe even some aquatic?) through two all-day schedules of demonstrations, activities, lessons and music. 11:30 to 5, both days.

Red Shed Community Garden (266 Skillman Ave. at Kingsland Ave.) in Williamsburg is holding a mega BBQ/benefit on Saturday, with $2 hot dogs, $3 burgers and sausages, free salads and sides, a raffle for dinners and services, a book swap and, oh, yeah, you get to see the workings of an urban organic garden. 1-6 p.m.

Sunday brings the kickoff the Jelly NYC Pool Parties at their new home in East River State Park (no pool here, but there’s some water nearby, so they kept the name). Still, there’ll be DODGEBALL, basketball, food and of course the DJs and bands. Sunday’s line up includes Mission of Burma, F***ed Up, Ponytail and Jemina Pearl. Gates open at 2 p.m., 90 Kent Ave. at N. 9th St.

Brooklyn Museum. Photo by Howard Brier

In Brooklyn, even the museums have insider secrets: like when you can go and not pay. Unbeknownst to many a culture hound, the Brooklyn Museum, Children’s Museum, Botanic Garden and the New York Aquarium all have special times during the week or month when you can wander in without reaching into your pocket. Without further ado…

Brooklyn Museum, 200 Eastern Parkway, 718-638-5000, www.brooklynmuseum.org
Normal admission: $10 suggested admission for adults and $6 for seniors and students. Free for children under 12. (Note that even everyday admission is “suggested.” We’ll leave it at that.)
Deals:The museum offers a same-day twofer “Brooklyn Art & Garden” ticket with the Botanic Garden for slightly less than what you’d pay for two admission tickets. $16 for adults, ($9 for seniors and students). On Target First Saturdays—the first Saturday of every month—museum admission is free, from 5 to 11.

Brooklyn Children’s Museum, 145 Brooklyn Ave. (at St. Marks Ave.), 718-735-4400, www.brooklynkids.org
Normal admission: $7.50 for adults, free for children under one.
Deals: Free before 11 a.m. on the second weekend of each month (Saturday and Sunday), and between 2 and 5 p.m. on Wednesdays through June 30.

Brooklyn Botanic Garden, 1000 Washington Ave., 718-623-7200, www.bbg.org
Normal admission: $8 for adults; $4 for seniors (65 and older) and students (12 and older)
Deals: Free all day on Tuesdays, amd from 10 a.m. to noon every Saturday. Free every weekday from (Nov. 20-Feb. 27).

New York Aquarium, Surf Ave. and West 8^th Street, 718-265-FISH, www.nyaquarium.com
Normal admission: $13 for adults; $10 for seniors (65 and older); $9 for children (3-12), free for kids under 3.
Deals: Pay what you wish on Fridays after 3 p.m.