In this video lesson, students will learn the meaning of the idiom "skeletons in one's closet" by using context clues. The teacher explains that idioms cannot be understood by looking at the meaning of each individual word, and encourages students to use surrounding words and sentences to figure out the true meaning. Through examples and explanations, students will understand that "skeletons in one's closet" refers to secrets from one's past that they want to hide from others.