Sky Is the Limit

There is no upper limit to what can be achieved

Paddle Your Own Canoe

To be independent and self-reliant

Teacher's Pet

A student who is the teacher's favorite

Cry over Spilt Milk

To be upset about something that has already happened and cannot be changed

Bite the Hand That Feeds You

To act badly toward someone who has helped you

Don't Judge a Book by Its Cover

Do not judge something by its appearance alone