A training accident makes Chloe's powers faulty; Max tries to cure her and gets a misleading positive result, so she goes to a party; but his treatment actually creates brand new powers Chloe can't control.
Chloe, Jinx and Booch are designing a school mascot, but Max and Phoebe's feud over their jobs ruins the project; Chloe criticizes them, and the twins realize their fighting affects Chloe now that they're guardians.
After Phoebe and Max let Chloe's friends watch a horror movie and eat candy, Jinx and Booch's parents want to meet Chloe's; Max and Phoebe transform into them to help Chloe; it goes well until the real Hank and Barb show up.
Cherry visits and Max discovers Phoebe never took her sparkle power away; Phoebe promises to do so and has a girls' night with Cherry while Max hosts Jinx.
A new super-fast villain is wreaking havoc in Secret Shores; after Billy's speed accidentally triggers an avalanche, he decides to hang up his cape and retire.
Max and Phoebe attend a parent-teacher night, leaving Chloe to have friends over without adult supervision; Jinx finds the Air Lair and believes spies are targeting the school and his meddling puts Max and Phoebe's school jobs at risk.
Chloe feels smothered and thinks it's because Phoebe and Max need friends; Phoebe and Max accidentally make the same friend named Brenda and fight over her.
Billy brings a new sidekick Steve to town and wants him to join the T-Force; Phoebe and Max agree to consider him, but when they eventually reject Steve for having a very lame power, he turns evil.
The Thundermans are visited by High Tide, the former protector of Secret Shores. He decides to take back his old role, even if it puts Jinx and Booch in danger.
Max seeks help dealing with a mystery prankster at school from his old principal, who was always the target of his pranks. But Max fails to stop the pranks, and the original prankster questions what's next.
Chloe struggles with her leadership skills; when a villain attacks her school field trip, Max and Phoebe have to put Chloe in charge while they try to take down the villain and defuse his dangerous astronomical weapon.
Chloe has been missing school by going on missions with her siblings. She now has to go to summer school to catch up on everything she has missed. Max, acting as the substitute for summer school, has a new student who agrees to tutor her.
B.C. invites Chloe to a launch party at Splat By-The-Sea, at the same time Jinx and Booch invite Chloe to protest outside the party. Meanwhile, Phoebe is keeping her work with Captain Perfect a secret.
Upset by Phoebe's secret partnership with Captain Perfect, Max decides to find a new superhero partner in his best friend, Gideon. However, things go awry when Max attempts to mold Gideon into a better superhero.
Max agrees to mentor Captain Perfect's younger sister, who is headed down the path of becoming a supervillain. She tries to become one of Mastermind's henchmen.
Max, who misses fame and attention, wants to make a name for himself again by breaking Booch's sandwich stack record. But Chloe wants to prevent her friend from losing the record title and challenges Max.
