This is NOT an idle game. After paying for no ads you still can't make money without clicking the bonus pop ups. After upgrading everything except premium staff it's impossible to reach 600 prestige without spending real money on diamonds or waiting weeks to build up enough diamonds to unlock all the premium staff. If you want to play the game without spending cash you'll get two schools that you can quickly max out. I'm happy to spend cash on entertaining games, this is merely a cash grab.