August 31

Last Blast Labor Day Prediction 5K. Runners predict their times; top 20 predictions win prizes. No watches, mile markers or clocks. 7:30 a.m. at Grove Park, Rehoboth Beach. Info: seashorestriders.com.

September 1

Summer’s End 5K, 7:30 a.m. at Jimmy’s Grille, Dewey Beach. Benefits the Dewey Beach Patrol, the Consortium in Lewes, and the Tyanna Foundation, a Baltimore-based group that helps people affected by breast cancer. Info: races2run.com.

September 2

Rylie’s Dog Days of Summer 5K, at the American Legion Post 17, Lewes. 8 a.m., kiddie race starts at 7:45 a.m. Benefits Rylie’s Smile Foundation, which provides iPod Touch computers to children who are facing life-threatening diseases. Info: races2run.com. For information about Rylie’s Smile: ryliessmilefoundation.org.

September 5

Run, White and Blue 5K. 6 p.m. at Del Tech, Georgetown. Includes a 1-mile walk. Benefits the campus’s Veterans and First Responders Scholarship. Info: seashorestriders.com.

September 7

Gary P. Lister Bottle & Cork Ten-Miler/5K. At the Bottle & Cork, Dewey Beach. 7:30 a.m. Benefits Dewey Beach Patrol, the Tyanna Foundation, and the Sussex Consortium. Info: races2run.com.

September 8

Cannonball 5K Run and Trenny Elliott Memorial Walk. 8:30 a.m. at the Lewes Historical Complex. Routes will go through historic Lewes. Sponsored by the Lewes Historical Society. Info: 645-7670 or historiclewes.org.

September 14

Dewey Beach Sprint Triathlon. Half-mile swim, 15-mile bike ride and 3.5-mile run. Other options: the duathlon — half-mile beach run, 16-mile bike ride and 3.45-mile run — and the aquabike — half-mile swim and 16-mile bike ride. Triathlon can also be run as a relay. At Delaware Seashore State Park, south of Dewey Beach, starting at 8 a.m. Info: deweybeachtriathlon.com.

Hustle for the House 5K, to benefit the Ronald McDonald House of Delaware. Kiddie K at 8:15 a.m., race starts at 8:30 a.m. at Irish Eyes restaurant, Lewes. Post-race party includes a costume contest. Info: rmhde.org.

September 20 through 22

Bethany Beach First Responders Sports Weekend. Includes a half-marathon, which can be run as a relay, triathlon (swim, bike and run), dualthon (run, bike and run), aquabike (swim and bike) and a 5K run. Benefits the Bethany Beach Volunteer Fire Company. Events all begin and end in downtown Bethany. Info: bethanybeachtri.com.

September 21

Paradise Crushin’ Cancer 5K run. Noon at Paradise Grill, Long Neck. Two courses, one along the water and the other more shaded. Info: seashorestriders.com.

September 22

Udderly Fun Mooo-Run. 9 a.m. at Hopkins Farm west of Lewes. The farm’s creamery will be open following the run. Benefits the Food Bank of Delaware; runners can bring canned goods with them to donate. Info: seashorestriders.com.

September 28

Taste of Sposato Wine 5K. 9 a.m. at Sposato Landscape Co., Hudson Road near Milton. Benefits the Sposato Family Vineyards Scholarship Fund, for students studying agriculture. Info: seashorestriders.com.

September 29

Dogfish Dash 8K, 9 a.m. at Dogfish Head Craft Brewery, Milton. Benefits the Delaware chapter of the Nature Conservancy. Info: dogfishdash.dogfish.com.