Let Sleeping Idioms Lie
Introduce students to 15 popular English idioms, and let them try to figure out their meanings based on the pictures and hints. This can be as simple as asking for volunteers, or forming them into groups, giving them white boards, and making a point game out of it.
Then let the students research their own idiom and present it to the class. A good list of resources is included below where they can find a ton of examples to choose from. For the presentation, I would again suggest small groups and instructing them to create a very short skit/act using their idiom in a way to convey to the meaning, and see if their classmates can figure out what the phrase means. Let the groups lead their short presentations and Q&A meaning checks by themselves as much as possible.