Today

National Youth Service Day

Fun service projects for families, entertainment and resource fair on local volunteer opportunities, by United Way of King County, 9 a.m.-4 p.m., Seattle Center Mural Amphitheatre, Seattle; free. 312-988-2354.

Fremont Library celebration

Dedication ceremony for reopening of renovated branch library, with zydeco music, kids' craft activities, noon-3 p.m., Fremont Library, 731 N. 35th St., Seattle. 206-386-4636 or www.spl.org.

Lewis and Clark Family Saturday programs

Hands-on program for families with children ages 5 and up focusing on native plants in the Washington Park Arboretum, 2 p.m., Museum of History & Industry, 2700 24th Ave. E., Seattle; $5-$7. 206-324-1126 or www.seattlehistory.org.

Greenwood Garage Sale

More than 150 garage sales in the Phinney/Greenwood neighborhood, 9 a.m.-3 p.m., maps listing all of the locations available online and at the Phinney Neighborhood Center, 6532 Phinney Ave. N., Seattle; free. 206-783-2244 or www.phinneycenter.org .

Star parties

Seattle Astronomical Society invites visitors to use its equipment to observe the night sky, weather permitting, rain cancels; dusk, at Green Lake Park on the north shore west of the Bathhouse Theater, 7201 E. Green Lake Drive N., Seattle, and at Paramount Park, Eighth Avenue Northeast and Northeast 155th St., Shoreline. 206-523-2787 or www.seattleastro.org.

April Pools Day

Free event with water-safety tips and activities in and out of the pool, and "hands-on" water safety for all ages, call individual pools for specific activities: 10 a.m.-noon, Ballard Pool, 1471 N.W. 67th St., Seattle, 206-684-7430;1:30-2:30 p.m., Evans Pool, 7201 E. Green Lake Dr. N., Seattle, 206-684-4961; 9:30-10:30 a.m., Meadowbrook Community Center, 10517 35th Ave. N.E., Seattle, 206-684-4989; 10-11 a.m., Medgar Evers Pool, 500 23rd Ave., Seattle, 206-684-4766; 10-11:30 a.m., Queen Anne Pool, 1920 First Ave. W., Seattle, 206-386-4282; 10 a.m.-noon, Lynnwood Civic Center Campus, 19000 44th Ave. W., Lynnwood, 425-771-4030; free lap swim, noon-1 p.m., open house 1-2 p.m., events 2-3 p.m., free public swim 3-4 p.m., Covington Aquatic Center, 18230 S.E. 240th St., Kent, 425-413-7665; 1-3 p.m., Kenneth Jones Pool, 30421 16th Ave. S., Federal Way, 253-839-1000.

Old-Time Country Dance

Family dance geared to young children, 5-6:30 p.m.; old-time country dance workshop, 7:30 p.m., dance party for adults and teens, 8-10:30 p.m., Island Center Hall, 8395 Fletcher Bay Road N.E., Bainbridge Island; $3-$8. 360-697-6192.

Leaping Lemur Day

Celebration of the lemurs of Madagascar with activities, information and special goodies for the lemurs, 9 a.m.-4:30 p.m., Cougar Mountain Zoo, 19525 S.E. 54th St., Issaquah; $6-$8.50. 425-391-5508.

Earth Faire at Northwest Trek

Information, family-friendly activities, games and crafts, tours, volunteer projects, 9:30 a.m.-6:30 p.m., Northwest Trek Wildlife Park, 11610 Trek Drive E., Eatonville; $5-$9.50. 360-832-6117or www.nwtrek.org.

Today, tomorrow

Whirligig

Last weekend for indoor carnival for kids with seven super-size inflatable rides, 11 a.m.-6 p.m. today and tomorrow, Seattle Center House, Seattle; $1.25/per ride, $6.50/all-day pass, $4/toddler pass ages 3 and younger. 206-684-7200.

Seattle Public Library Book Sale

Sale of more than 125,000 books, CDs, records, videos, sheet music, art prints and posters, most priced 50 cents-$1; preview for Friends of the Library members only, 9 a.m.-5 p.m. today, 11 a.m.-4 p.m. tomorrow, Sand Point Magnuson Park, 7400 Sand Point Way N.E., Seattle; free. 206-523-4053.

Puyallup Spring Fair

Junior livestock show, vendors, entertainment, kids' activities, petting farm, floral displays and garden show, kiddy rides, thrill rides, pig races, 10 a.m.-10 p.m. today, 10 a.m.-7 p.m. tomorrow, Western Washington Fairgrounds, 110 Ninth Ave. S.W., Puyallup; $6-$8. 253-845-1771 or www.thefair.com.

Tulip Festival Street Fair

Juried arts-and-crafts vendors, food and music, 10 a.m.-7 p.m. today, 10 a.m.-5 p.m. tomorrow, Mount Vernon. 360-428-5959 or www.tulipfestival.org.

Tomorrow

Puget Sound Baby and Children's Show

Maternity and children's fashion shows, entertainment, speakers, information for parents and activities for children, 10 a.m.-6 p.m., Seattle Center Northwest Rooms, Seattle; free. 206-684-7200.

April Pools Day

Free event with water-safety tips and activities in and out of the pool, and "hands-on" water safety for all ages, call individual pools for specific activities: 3:30-5 p.m., Helene Madison Pool, 13401 Meridian Ave. N., Seattle, 206-684-4979; 12:30-2:30 p.m., Rainier Beach Pool, 8825 Rainier Ave. S., Seattle, 206-386-1944

Tuesday

Kids Discovery Museum

Opening day of new 3,700-square-foot museum for children through age 8, with displays, theater for dramatic play, hands-on art room and "wacky science" programs, 10 a.m.-5 p.m.; community celebration and ribbon-cutting, 10 a.m.-4 p.m. April 23; regular hours 10 a.m.-5 p.m. Tuesday-Friday, 10 a.m.-4 p.m. Saturday, 1-5 p.m. Sunday, Kids Discovery Museum, 305 Madison Ave. N., Bainbridge Island; $5. 206-855-4650 or www.kidimu.org.