Things to do this weekend: Huge haunt fests summon big Halloween thrills

Haunted Events Aplenty: There's a sudden chill in the air — quite literally — as we head for the start of fall, which must mean some of the biggest Halloween-themed events in SoCal are impishly revving up. We're not (too) scared: Knott's Scary Farm in Buena Park, the Queen Mary's Dark Harbor, and Los Angeles Haunted Hayride in Griffith Park are all ghostily floating into the first weekends of their 2024 runs.

Kidspace Halloween Bash: Seeking some daytime family fun inspired by the fall occasion? This Pasadena educational museum will have daily — yes, daily — costume parades made for the littlest Halloween fans as well as autumn activities. There are two parades on weekdays and three on weekends; it all begins Sept. 20, concludes Oct. 31, and advance tickets? Very much recommended.

California Coastal Cleanup Day: If you're especially sweet on a particular stretch of spectacular sand, riverbank, or lakeshore, you're invited to spend the morning of Sept. 21 giving it a good tidy-up. This huge volunteer event is happening up and down the coast and inland, too. Check the map to find and join an event (there are oodles), then check the supplies you'll need to bring along.

Frogtown Artwalk: Frogtown is always pretty darn fanciful, as its wonderful name so strongly suggests, but when this art-forward happening comes back around, the imagination flows like the river that the community famously borders. Enjoy gallery shows, musical moments, hands-on activities, and plenty of creative fun Sept. 21. And, oh yes, it's free.

Great Pumpkin Weigh-Off: Send out summer in a big way — make that a gargantuan way — at Irvine Park Railroad, where some of the most sizable squashes around will hit the scales (gently, of course). Major prizes and cash are involved in this charming tradition, which pays admiring tribute to a cavalcade of tenacious growers. Get "pump"-ed Sept. 21 in Orange.