Spinechillers Mysteries Series by Fred E. Katz

Kyle Conlon discovers that a bizarre carnival has mysteriously appeared overnight right next door to his uncle's house. He and this three friends, Sara, Sammy and Brent, set out to investigate.The carnival's owner, Dr. Shivers, invites the four of them to try all the amusements for free - if they're brave enough.

Anna and Johnny Greger are looking forward to a quiet day at home. When Jonny's science project - a robot - attacks Anna, she thinks it's just Johnny playing a joke. But she knows something is terribly wrong when her hair dryer flies, their video game shoots back at them, and the lawn mower takes off on its own. But a house can't attack people. Or can it?

Just before leaving with his parents to go skiing before Christmas, Connor Morgan breaks his leg. Fortunately, Great Aunt Bergen is coming to watch the house, and Conner can stay with her.But there is something very strange about Aunt Bergen, and strange things start to happen when she arrives.

It's MacKenzie's twelfth birthday. He'd like a paintball party, but his mom books the party at Spookie the Clown's Hall of Pizza. Unlimited play on the video games makes it pretty cool, until Spookie shows up with some games of his own. Soon, all the kids want to win is a chance to get out