By John RittenhouseA Hills-Beaver High School senior has been invited to participate in the Special Event during the annual Howard Wood Dakota Relays in Sioux Falls Friday.Cassi Tilstra, an H-BC standout runner, will be one of eight entries in the Girls 400-Meter Dash, which is the Special Event for the 2005 meet.The daughter of Arlyn and Melanie Tilstra will run in Lane No. 1 during the 7:40 p.m. race.Tilstra and Allie Smith of Wahpeton, N.D., are the seniors in the field.Juniors include Mitchell Christian’s Andrea Nielsen, Lead-Deadwood’s Breynn Feterl and Bridgewater-Emery’s Heather Wollman.Sophomores in the field are Rapid City Steven’s Samee Pagel, Gayville-Volin’s Emma Erickson and Parker’s Abby Plucker.All the juniors and sophomores represent South Dakota Schools.