This is perhaps one of Shakespeare's more interesting plays, if you will. In comparison to Macbeth it isn't quite the walk in the park.
I think conceptually it enables the reader to see that characters can influence characters to such a degree that the original traits are masked and changed. Tragedy in this play is definitely a main component - and a great emphasis that perhaps the villain doesn't always find their true defeat. In a way, wasn't the "villain" successful? He lied to everyone and pretty much killed whomever got in his way.
The perfect classroom. Ask students to write a paragraph that tells what they think the perfect classroom should be like. (This is not fiction/fantasy writing; they should describe the atmosphere of an ideal real classroom.) Arrange students into groups of four. Ask each student to underline in his or her paragraph the "most important words or phrases." After students have done that, they should pass their papers to the person in their group who is seated to their right. Students should continue passing papers and underlining important words until the original writer has her/his paper back. At that point, students will share with the group some of the important words and phrases in their own writing; a group note taker will record the words and phrases that might best describe a perfect classroom. Group members will review the list and decide on five words or phrases to share with the class. When the class has a fully developed class list of words and phrases, they will use some of those words and phrases to write a "class statement" that will be posted on the wall for all to see. When things are not going "perfectly," it is time to review the class statement.