DUNWOODY

Sci Fi Summer Con

From Red Shirts to Admirals, Padawans to Masters, this is one convention the ET in you won’t want to miss. Sci Fi Summer Con includes movie screenings, trivia games, costume contests and book signings, as well as a Nerf gun shootout, Super Soaker duels, a charity poker tournament and a rave party. Several panel discussions will explore paranormal investigation, conspiracy theories, voice acting and novel writing. Merchandise dealers also will be on-site. Attendees can opt for a one-day visit or pick up a weekend pass.

6 p.m.-midnight June 12, 9 a.m.-midnight June 13, 9 a.m.-6p.m. June 14. $35 for the entire event; $10 for Friday or Sunday; $20 for Saturday. Children younger than 12 are free. Holiday Inn North Perimeter, 4386 Chamblee Dunwoody Road, Atlanta. 770-313-9237, sfscon.tripod.com.

ROSWELL

Back to the Chattahoochee River Race & Festival

Come paddle on and celebrate Atlanta’s main waterway. Begin at 9 a.m. at Garrard Landing in Alpharetta by racing a kayak, canoe or paddleboard eight miles down the river to Roswell’s Riverside Park, where a free festival kicks off at 10 a.m. The celebration features local artists and farmers market vendors, along with live music and activities for the kids — a Frisbee dog demonstration, face painting and balloon artists. Proceeds support the Chattahoochee River

9 a.m. race kickoff; 10 a.m.-3 p.m. festival. June 13. $70-$90 for the race; free admission to the festival. Riverside Park, 575 Riverside Road, Roswell. 404-352-9828, chattahoochee.org.

McDONOUGH

Art in the Park

Whether you’re an expert or amateur, you’re invited to exhibit your creative talents at McDonough’s Art in the Park event, held on the scenic town square. McDonough Arts, a community support group, hopes the event will enable artists to sell some of their works and encourage others to pick up a brush and get painting. The event also will feature the Plein Air Paint-Out, where artists will work on projects out in the fresh air for two hours. Afterward, the new paintings will be judged, and prizes will be given to the winners.

Noon-4 p.m. June 13. Free admission. McDonough Square, 5 Griffin St., McDonough. 706-537-1564, mcdonougharts.net.