So I recently went on a buying spree for items to use in my de-spooking and bombproofing work on my young horse who developed an over-active startle reflex. (Is that a thing? I think I just invented it! As in, "Oh no sir, he ain't spooky, he just has a light case of OASR.")
At any rate, he had a few experiences that made him much more jumpy than his actual personality should warrant. For example, I wear an air vest. One day while riding with friends, I unthinkingly jumped off my horse (Atticus) to pick up a dropped whip. I totally forgot about my vest, and it inflated with a bang. The youngster shied sideways at the sound, and his rider came off, which further frightened him into believing the world was ending. For several rides afterwards, whenever I would dismount Atticus, the youngster would tremble, ready to take off. Had I not witnessed the precipitating event, I might have had no idea why he seemed to have such a strange phobia, but there you go.
Anyway, I reviewed some of my prior horse training notes and did a little internet research, and found the best thing for him was showing him "scary" things, and convincing him to trust his handler or rider, and that way his reaction time would become shorter and shorter to new and frightening stimuli. So here are some of the fun things I got:
Party noisemakers - These fun little mechanical things that twirl around on a stick, and actually do have slightly different sounds. Cheap and portable.
Little colorful wind spinner thingies... So far I have just sort of waved these around, but I think maybe I need to drill some extra holes in a jump standard and have them poking out all over.
Bumble Ball - Another toy to sit in the low plywood box. (Actually, I found something that would probably work better than the box that you can also order on Amazon! Try this dog crate tray. You're welcome). Makes super erratic, jumpy movements, sure to scare the Bejeezus out of any horse! Apparently more or less the same as the Chuckle Ball, but a little smaller. Take your pick, I suppose.