(as) bright as a new penny

1. Shining, gleaming, or reflecting very brightly and clearly. I want you to wash the car and polish it till it shines as bright as a new penny! What, did you run out of shoe polish? Why is only one of your shoes bright as a new penny? I got my engagement ring professionally cleaned and, boy, is it bright as a new penny now!

2. Especially intelligent, astute, or perceptive. Your daughter is such an excellent student. She's always so eager to participate and is as bright as a new penny. My granddad may be old and cantankerous, but he's still bright as a new penny. You can't get anything past him. Ted's as bright as a new penny, so he'll find a solution to this problem.