Relay for Life Yard Sale

Raise money for Relay for Life team Infinite Survival by browsing household items and knickknacks at a yardsale. 7am-1pm @ Calvert County Fairgrounds, off Rt. 231, Prince Frederick: 410-414-5222.

Berry Fun

Celebrate the strawberry at the Waters Memorial Church Strawberry Festival, featuring ice cream, sandwiches, seafood platters and a culinary salute to the strawberry. Browse items at a yard sale (7am); feast on fresh-picked strawberries; and craft your own keepsake at art tables. noon-6pm @ Waters Memorial United Methodist Church, 5400 Mackall Rd., St. Leonard: 410-586-1716.

The Best of Breezy Point

Browse yard-sale wares, craft creative gifts at art tables and purchase handmade flower arrangements at Breezy Point’s Community Sale. Test your luck buying raffle tickets for prizes ranging from boat ramp passes to wine baskets. 8am-1pm @ Breezy Point, off Rt. 261, near Chesapeake Beach: 410-535-9311.

Yard Sale

Find bargains at the rummage tables of St. Andrew’s Church. At the homemade soup table, pick up a quart or gallon for dinner. 8am-1pm @ St. Andrew’s United Methodist Church, 4 Wallace Manor Rd., Edgewater: 410-269-7671.

Hazard a Trip

Purge your house of hazardous chemicals without tossing toxic products into landfills at this monthly drop-off sponsored by A.A. County. Hazardous household chemicals accepted include: pesticides, oven cleaners, wood preservatives, flammable liquids, oil-based paint and more. 8am-2pm @ Glen Burnie Convenience Center, 100 Dover Rd., Glen Burnie: 410-222-7951.

Help Our Heroes

Browse white elephants, snack on carnival fare and play games all day to raise money for wounded troops in Walter Reed. Meet South County Chamber of Commerce Gene Hall-award winner Pam Parks at this fundraiser to buy phone cards for wounded veterans. 9am @ Beside Parks’ Liquors, 454 Rt. 258, Deale: 410-867-4577.

Reduce Pollution with Rainscaping

Learn how to help the Bay in your own backyard with the Severn River Association’s rainscaping workshop. Discover which plants can reduce runoff, browse blooms at a native plant sale and pick up a rain barrel for stormy- weather savings. 9am-1pm @ Pines on the Severn Playground, 181 Severn Way, Arnold: 410-451-4297.

Hike Through History

Take a walking tour of downtown Annapolis and discover the history behind the buildings and streets. Stops include Banneker Douglass Museum, William Paca House and City Dock. 10am-2pm @ Chesapeake Children’s Museum, 25 Silopanna Rd., Annapolis. $15; rsvp: 410-990-1993.

Boating Safety Week

Cruise local waters with caution at the kick-off of Safe Boating Week. Have your vessel examined by state-certified Auxiliarists and members of the US Power Squadron; see a A.A. County fireboat in action; watch a Coast Guard rescue demonstration; and bring the kids to meet talking safety robot, Coastie. 8am inspections; 10am-4pm fair @ Sandy Point State Park, near Annapolis off Rt. 50, near Annapolis: 301-840-2248

Wage War on Weeds

Enlist with Patuxent Park’s weed warriors to pluck invasive species from the wildlife habitat. Bring gloves and water. 9am-noon @ North Tract, Patuxent Park, Rt. 198, between Rt. 295 & Rt. 32, Laurel. rsvp: 301-497-5887.

Shred-a-Rama

Rend your important documents to bits, preventing identity theft at the second annual Shred-a-Rama. A.A. County police help you feed documents into a commercial shredding truck, destroying tax records, medical records and financial documents that could lead to identity theft if thrown in a conventional garbage can. 410-222-1401. 9am-1pm @ four locations:

• Parking lot, South River High School, 200 Central Ave., off Rt. 214, Edgewater.

• Parking lot, old Ames Department Store, 8107 Rt. 2, at Jumpers Hole Rd., Glen Burnie.

• Parking lot, Cancun Cantina, 7501 Old Telegraph Rd., Hanover.

• Parking lot, Brooklyn Park Middle School, 200 Hammonds Ln., Brooklyn Park.

Tour Thomas Point

Cruise out to Maryland’s only screwpile lighthouse still in its working location: Thomas Point Shoal Lighthouse. Take a docent-led tour inside the historic landmark and learn how the structure was restored. Also May 18. 9am, noon & 3pm @ The Barge House, Annapolis Maritime Museum, 723 Second St., Eastport. $70; rsvp: 800-690-5080; www.annapolismaritimemuseum.org.

Paddle Out or Wade In

Meet the researchers of the Smithsonian Environmental Research Center at an open house and learn how you can save the Bay. Paddle for supremacy at a West Riverkeeper Kayak Race (9am); wade into the river for a hands-on aquatic health check (11am); listen to live music all day; and climb a solar radiation tower. Kids visit face painters, play games and take hayrides. 9am-3:30pm @ Smithsonian Environmental Research Center, 647 Contees Wharf Rd., Edgewater. $2 donation; $15/kayak race entry: 443-482-2300.

Paddle Safely

Canoe with confidence at a flat-water workshop and learn to paddle through a variety of water conditions and safety hazards. Bring a complete change of clothes and a lunch. 9am-3:30pm @ Jug Bay Wetlands Sanctuary, 1361 Wrighton Rd., Lothian. $40; rsvp: 410-741-9330.

Race for Special Olympics

Lace up your tennis shoes and raise money for Southern Maryland’s Special Olympics with a 5K run/walk. Competitive racers fly through a course marked by the Calvert County Sheriff’s Office while leisurely fundraisers meander through scenic Solomons. 9am registration; 10am race @ Calvert Marine Museum, Solomons. $25: 410-535-2857; www.somdcalvert.org.

Compost Workshop

The Anne Arundel County Master Gardeners teach you how to turn kitchen scraps and bio-degradable material into rich soil at a composting class. 10am @ Quiet Waters Park, 600 Quiet Waters Park Rd., off Hillsmere Dr., Annapolis. $5: 410-757-7780.

Stuff Toys with Hugs

The first 150 visitors to Build-a-Bear Workshop stuff a white puppy toy and donate it to one of three charities — SuperSibs!, Sunshine Kids Foundation, or Pet Shelters Across America. 10am @ Build-a-Bear Workshop, the Westfield, Annapolis: 410-897-0828.

CYSO Season Finale

The Chesapeake Youth Symphony Orchestra ends its symphonic season with two concerts. First, the Concert Orchestra, Preparatory Strings Orchestra, Strings and Junior Flute Ensemble bow through a selection of classical music. Second, the Symphony Orchestra, Wind Ensemble and Sr. Flute Ensemble play selections from the silver screen featuring Harry Potter and Pirates of the Caribbean. 3pm & 7pm @ Riva Trace Baptist Church, 475 Central Ave., Davidsonville. $12 w/discounts: 443-758-3157.

Compost Competently

Master the rotten business of composting with the help of master gardener Katherine West. Tour the Community Resources Building for more composting ideas. 10am @ Calvert County Community Resources Building, 30 Duke St., Prince Frederick: 410-535-0291.

Learn Heirloom History

William Paca garden director Mollie Ridout speaks on the origins of heirloom roses in the garden, and head gardener Roger Galvin shows you which roses need least maintenance in a home garden. 10-11am @ William Paca Garden Terrace, 186 Prince George Street, Annapolis. $10: 410-990-4539.

Search the Cosmos

Learn how to use library data search program Cosmos and make your next research project easier. 10-11am @ Calvert Library, Market Square, Prince Frederick: 410-535-0291.

Set off Sparks

People from ages 10 up learn how to make fire using a bow and drill. All children must be supervised during the lesson. 10am-noon @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. free: 410-586-8501.

Bayscape Your Backyard

Learn how to make your backyard green — literally and environmentally — with a workshop on transforming your land into a Bayscape. 10am-3pm @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. $8/person; $20/family: 410-586-8501.

Honor Heroes

County Executive John R. Leopold honors A.A. County soldiers lost during the war on terror on Armed Forces Day. Leopold speaks on the soldiers at a flag ceremony in a newly planted memorial grove of dogwood trees. 11am @ Fort Smallwood Park, 9500 Fort Smallwood Rd., Pasadena: 410-222-1821.

Open Waters

Take a dip at the refurbished Chesapeake Beach Water Park as it opens for the season. Get your fill of aquatic fun, splash around in fountains, waterfalls, a lagoon, kids’ activity pool, water volleyball area and more. Speed down eight waterslides for a wild wet ride.11am-8pm @ Chesapeake Beach Water Park, 4079 Gordon Stinnett Ave., Chesapeake Beach. $10/local; $18/visitors: 410-257-1404; http://chesapeakebeach.md.us/majorattractions_waterpark.htm.

Learn Herbal History

Take a culinary history lesson on the uses and health benefits of popular cooking herbs. 1pm @ Comfort Station, Kinder Farm Park, 1001 Kinder Farm Park Rd., off Jumpers Hole Rd., Millersville. rsvp: 410-222-6115.

Slice into Apple Programs

Join Annapolis Apple Slice for a workshop on Mac OS X versus OS 10.5 with expert Dave Marra. 1-4pm @ Severna Park Library, 45 McKinsey Rd., Severn Park: 410-695-0112.

Jefferson Patterson Park

Ages 10 and up wander through the home and gardens of Jefferson Patterson Park and Museum, learning how volunteers are restoring the property. Take a turn around the Rose Greely-designed gardens and visit Jefferson Patterson’s colonial revival brick house, designed by Gertrude Sawyer. Also May 18. 2pm @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. $10; rsvp: 410-586-8501.

Spring Dinner

Feast on crab cakes and ham to fund the parish’s missionary work at the annual St. James’ spring dinner. The festivities expand this year to include a children’s fair, moonbounce and games. Carryout available. 2-6pm @ St. James’ Episcopal Church, 5757 Rt. 2, Lothian. $18: 410-867-2838.

Pig Out

Feast on pork at a seven-pig cook off to aid the Taylor family’s medical expenses. Mitch Harrell and the Hole in the Wall Band perform live while you compete in a horseshoe tournament and play fair games. 4-10pm fair; 5-8pm food @ American Legion Post 226, 830 Central Ave., Mayo. $25 w/discounts: 410-798-9894.

Dust off Your Do-Si-Do

Seasoned steppers and novices square off as caller Laura Brown leads you through a night of contra and square dancing. Alexander Mitchell and Paul Miller provide live music; early birds get a free lesson. 6:30pm lesson; 7-10pm dance @ Annapolis Friends Meeting Hall, 351 Dubois Rd., Annapolis. $10 w/discounts: 301-717-6454.

Prowl for Owls

Find out who says who at night when a naturalist leads a nocturnal hike, tracking down owls, frogs and other night dwellers. 7:30-9:30pm @ North Tract, Patuxent Park, Rt. 198, between Rt. 295 & Rt. 32, Laurel. rsvp: 301-497-5887.

Tour Thomas Point

Cruise out to Maryland’s only screwpile lighthouse still in its working location — Thomas Point Shoal Lighthouse. Also May 31. 9am, noon & 3pm @ The Barge House, Annapolis Maritime Museum, 723 Second St., Eastport. $70; rsvp: 800-690-5080; www.annapolismaritimemuseum.org.

Safe Boating Day

Learn the right way navigate at safe-boating day. Watch a rescue squad demonstration, meet local Coast Guardmen and women and ask safety questions of experts. 10am-2pm @ Solomons Volunteer Rescue Squad and Fire Department, HG Truman Rd. & Dowell Rd., Solomons: 301-247-7238.

Celebrate the Centiquinquennial

Heritage Baptist Church celebrates 105 years of worship with a ceremony at the 10:30am service featuring a speech from former pastor Dr. Fred Moffatt. Then, sit with the parishioners for a community supper and an informal hymn sing. 10:30am worship; noon supper; 1:15pm hymn sing @ Heritage Baptist Church, 1740 Forest Dr., Annapolis: 410-263-6680; www.heritagebaptistonline.com.

Chesapeake Beach Railway Museum Spring Fest

All aboard for fun in the sun in two locations as Chesapeake Beach Railway Museum celebrates the season. At the museum, examine wooden trains, color an engine, search for treasure on a scavenger hunt, and watch Abigail Francisco’s ballet students twirl through a performance. Kellam’s Ball Field features carnival rides, fair games, face painting and clowns. Try for water park tickets at a raffle.

• 12:30-3:30pm @ Kellam’s Ball Field

• 12:30-4pm @ Chesapeake Railway Museum, adjacent to Rod ‘n’ Reel, Chesapeake Beach: 410-535-1326

Visit an Indian Village

Discover life in an Eastern Woodland Indian Village by helping maintain a longhouse, making primitive tools and learning ancient gardening techniques. 11am-3pm @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. free: 410-586-8501.

Salute the Lost at Solomons

Pay homage to the water people who lost their lives at the annual wreath laying ceremony at the Solomons Waterman’s Memeorial. Snack on pastries from Tidebox, listen to the National Anthem, pledge allegiance to our flag, watch the wreath laying and bow your head as trumpeters play Taps. Later, stop by the Solomons Island Yacht Club for the 1pm blessing of the fleet.

• 10am @ Waterman’s Memorial, Solomons: 410-326-3166.

• 1pm fleet blessing @ Solomons Island Yacht Club, 14604 Rt. 2, Solomons.

Vintage Baseball

Turn back the clock to 1864 as the Chesapeake Baseball Club slugs through a 19th century baseball exhibition game. 12:30pm @ Prince George’s Stadium, 4101 Crain Hwy., Bowie: 301-464-4865; www.baysox.com.

Organ Concert

Larry Molinaro plays the last Bach organ concert of the season, featuring Clavier-Ubung II as part of the St. Anne’s Concert Series. Playing the Feiburger organ, Molinaro kicks off the city’s afternoon re-dedication of the historic Southgate Fountain. 1pm @ St. Anne’s Episcopal Church, 199 Duke of Gloucester St., Annapolis. $15: 410-280-5640.

Bee & Season

Learn the spicy secrets of the Herb Ladies, who share herbal remedies from colonial times. Hear the buzz about bee keeping from demonstrators throughout the gardens and taste the honeyed fruits of their labor. 1-4pm @ Hancock’s Resolution, 2795 Bayside Beach Rd., Pasadena: 410-255-4048.

Cruise to a Car Show

Show off your vintage car or browse the competitors at the College of Southern Maryland’s car show. Vote for your pick in three categories: best car, best truck and best in show. 1-5pm @ College of Southern Maryland, Prince Frederick Campus, 115 J.W. Williams Rd., Prince Frederick. free: 443-550-6022.

Explore Jefferson Patterson Park

History buffs ages 10 and up wander through the home and gardens of Jefferson Patterson Park and Museum, learning how volunteers are restoring the property. 2pm @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. $10; rsvp: 410-586-8501.

Sail the Bounty

Leave from the Rod ‘n’ Reel docks for an afternoon cruise on the Bay, setting a course for Tilghman Island aboard the Bounty Hunter. Sup at Harrison’s Chesapeake House and watch the sun set over the water as you return. Tickets at all branches of the Calvert Library. 2-6pm @ Rod ‘n’ Reel Dock, Chesapeake Beach. $55; rsvp: 410-535-0291.

Concert for Communities

Jazzman Rob Levit plays a guitar concert benefiting the Creating Communities project, dedicated to joining neighbors through art and expression. 3pm @ St. Luke’s Episcopal Church, 1101 Bay Ridge Ave., Annapolis. $20; rsvp: 410-268-5419.

Southgate Memorial Fountain

See the flow return to Southgate Memorial Fountain as the city of Annapolis rededicates the restored landmark. Mayor Moyer dedicates the fountain, and Annapolis Chorale and community choirs serenade you. 3pm @ St. Anne’s Episcopal Church, 199 Duke of Gloucester St., Annapolis: 410-280-5640.

Tea for Two

Mother and child sip from china cups and learn the traditional ceremonies in a tea service at a belated Mother’s Day celebration. Pose for a picture with mom, read poetry and snack on treats at a tea benefiting Barstow Acres’ work with differently abled children. 3-6pm @ Emmanuel Baptist Church, 3800 Old Town Rd., Huntingtown. rsvp: 410-414-9901.

Hunt for Herps

Take to the trails with a guide, searching for reptiles and amphibians. 2-3:30pm @ North Tract, Patuxent Park, Rt. 198, between Rt. 295 & Rt. 32, Laurel. rsvp: 301-497-5887.

Spin By

Wool wonders never cease at a spinning and weaving demonstration where you get to take up the wheel and try your hand at creating skeins of wool. 2-5pm @ Jefferson Patterson Park & Museum, 10515 Mackall Rd., St. Leonard. free: 410-257-0769.

Join the Community Chorus

The Chesapeake Community Chorus raises voices in praise in a concert of classic and contemporary Christian music benefiting Burnett-Calvert Hospice House. 5pm @ Mt. Harmony United Methodist Church, 155 East Mt. Harmony Rd., Owings. donnation asked: 410-257-2761.

Music for Ministry

Support the ministry work of St. Martin’s Lutheran Church at a violin concert featuring Nick Drumm and Erik Apland. 7pm @ St. Martin’s Lutheran Church, 1120 Spa Rd., Annapolis. $8: 410-672-2452.