Charlie has lots of ideas. Need something to go sky high? Ah-ha! The zinger-winger! Need to launch a cheese popper into soup? The amazing popper-upper! But the zinger-winger zings more than wings and the popper-upper plops. Charlie isn't allowed to invent for a week. Meanwhile, the afterschool invention fair is coming up. He needs time to make something special. Good thing he has his friends and Mr. Redfern, another inventor, to help him out.