go bananas
 

go bananas go crazy, go nuts (slang), go insane, go bonkers (slang, chiefly Brit.), go mental (slang), go barmy (slang), go loopy (informal), go round the bend (Brit. slang), go frantic, go batty (slang), go doolally (slang), go round the twist (Brit. slang), go nutty (slang) People went bananas with boredom.