Peter thought the dentist was pulling his leg when he told her that she had 10 cavities. What does "pull someone's leg" mean?

Nathalie told her mom that she forgot to bring her report card home. Her mom didn't really believe her, but decided to give her the benefit of the doubt. What does "give him the benefit of the doubt" mean?

Susie had a really tiring day. She woke up early, went to school all day, then she had a to go to a friend's house to work on a project. That night, she couldn't wait to hit the sack. What does "hit the sack" mean?

Peter and his friends wanted to build the best racing cart for the race, but their cart broke when going down a steep hill. They needed to go back to the drawing board to make a new cart. What does "go back to the drawing board" mean?

Larry was excited to be a part of the musical. He would be playing a big part in it and he felt nervous. The show was about to start and his teacher told him to break a leg. What does "break a leg" mean?

Stephan wanted to buy stocks for the big company while prices were low but missed the boat. What does "missed the boat" mean?

Bob worked hard to learn the new math process. His teacher checked his work and told him he was on the ball. What does "on the ball" mean?

Mary didn't get to go on the field trip to the zoon, but that was a blessing in disguise because it started raining and everyone had a terrible time. What does "a blessing in disguise" mean?

Patrice hated working hard. She was upset when she didn't get chosen as her class representative. Her mom told her, "well, you didn't really work at getting the position. No pain, no gain." What does "no pain, no gain" mean?

Patrick went to a big company to try to get them to support his new great invention. The company dismissed his idea, saying that there were thousands of others like it. His idea was a dime a dozen.What does "a dime a dozen" mean?