• The Hacker’s Hill 4-Mile Preservation Walk and Run will be held at 8:30 a.m. Saturday in Casco. Proceeds benefit the protection of the scenic hilltop. Cost is $20 for adults, $15 for under 18. Registration begins at 7:30 a.m. For more information, visit www.runreg.com/Net/3208.

• The Summer Slammer Obstacle Run will be held at 9 a.m. Saturday at the My-Fit-24 fitness facility in Gorham. The 2.5-mile course includes mud, trails and obstacles. A half-mile course for children, including tunnels and hurdles, starts at 8 a.m.

• The Alvin Sproul Samoset 10K will be held at 8 a.m. Sunday at the Bristol Consolidated School. The race benefits the Bristol Volunteer Fire and Rescue Department. A walk will precede the race at 7:30 a.m., and a 1-mile fun run for kids 14 and under will follow at 9:30 a.m. Registration begins at 7 a.m. For more information, contact Dan Mocarski at 677-3666 or danmosr@midcoast.com.

• Practices for fall sports at Portland High begin Monday at the following times: football, field hockey and cross country, 8 a.m.; golf, 9 a.m.; boys’ soccer, 10 a.m.; girls’ soccer, noon; cheering, 3 p.m.

Practices will be held at Fitzpatrick Stadium, except for field hockey at the Deering Oaks baseball field and golf at Riverside Golf Course.

• Practices for fall sports at Freeport High begin Monday at the following times: football, soccer and field hockey, 8 a.m.; cross country, 5 p.m.; golf, 3:30 p.m. at Toddy Brook; cheering, 8:30 a.m.

Football equipment will be issued at 6 p.m. Sunday.

• Practices for fall sports at Kennebunk High begin Monday at the following times: soccer, 7 a.m.; football 7:30 a.m.; cheering and field hockey, 8 a.m.; cross country, 9 a.m.; volleyball, 6 p.m.

Golf will begin at 5 p.m. Aug. 16 at Hillcrest Driving Range.