“nose around” = look for something private or hidden
“The kids sometimes nose around the house for Christmas gifts.”

“umpteen (also, umpteenth)” = a great number of
“I have umpteen presents to buy before Christmas Eve.“

“crack a book” = to open books to study (usually a negative meaning)
“Brandon hardly ever cracked a book in high school, but he still was able to graduate.”

“cut class” = to skip school
“Why do you always cut class? You won’t pass the class if you do.“
“on the spur of the moment” = without planning or preparation
“I decided to go to the party on the spur of the moment, so I threw on some clothes and left.”

“be decked out” = be dressed in formal clothes for nice occasions
“She was decked out in a beautiful dress, and everyone was surprised.”

make sense (idiom): have a clear meaning or a sensible explanation
– It makes sense to ask teachers to wear a nice shirt and tie to work.

“pass with flying colors” = pass a class or test with high marks
“Many students passed the test with flying colors.”

“drop out of school” = stop attending school; quit school
“My sister dropped out of school because she didn’t have money to pay for tuition.”

“a walking encyclopedia” = someone who seems to know everything
“My roommate would do well on a trivia game show. He’s a walking encyclopedia.”

“have the right stuff” = have the needed skills to succeed
“Susan has the right stuff to get into any school she chooses.”

“burn the candle at both ends” = work to excess that affects your physical and emotional well-being
“It’s just not wise to burn the candle at both ends; it’s just impossible to work full time, go to school, and spend time with family.”

“work one’s tail off” = work very hard
“I have to work my tail off just to pay my rent.”