if the kitties are young, they're just packed with energy. trying adding some toys that they can get they're kitty aggression out on. stuffed animals work well. for example, next time you find your cat attacking something, replace it with a stuffed animal. play with them and the stuffed animal so they know it is okay to attack the stuffed animal. also, like larke said, move dangerous things out of the way until they learn. pennies in an empty water bottle works well-- when they're on top of your dresser knocking things off shake the bottle and it'll scare them. as long as they don't realize it's coming from you, they'll associate the noise witht he action and hopefully not repeat the action after a while.
especially with kittens it takes time to train them to not be destructive. are they left alone often? cats are very social, they like to be around people. trying playing with your cats. if they seems angry, hence they're destroying things to get back at you (maybe for not being around, bringing a new cat in, etc.) then there are herbal things to give cats that often calm them down.
more info would help answer your problem. good luck!