I make copies of this and cut them to give each student one at the beginning of class each day. They write the DLO at the top of the slip at the beginning of class, and at the end it is the closure activity for them to color in the correct traffic light color (red-stop, yellow-proceed with caution, or green-go) to designate how well they feel they've accomplished the objective. Then they explain what they still need explained or write something they've learned or gotten better at.
I have another version of it which is meant to be used as the Bell Ringer as well. It has lines on the back for them to write the answer to the Bell Ringer, which is projected (or written) on the board as they enter class - can be a question, math problem, short writing assignment, grammar activity, etc.