Ending the lesson (concluding, learners’ reflection, fillers) Who among esl teachers does not understand the purpose behind a warm up activity?

Ending the lesson (concluding, learners’ reflection, fillers)
Who among ESL teachers does not understand the purpose behind a warm up activity? We all agree that it’s important to get students focused, to introduce a task or topic, to break the ice, or simply place your students in “English mode”.
But what about cool downs?
Many teachers are not aware of the importance of a cool down. And what is exactly this importance?
Many teachers just play a game or let students work on an activity till the bell rings. When you do this you neglect to give your students closure on what they have learned for the day. You’re not capitalizing on your unique opportunity to effectively wrap things up in a way that will benefit your students’ learning.
The warm up and the cool down are like the introduction and the conclusion of an essay.
An essay with no conclusion has a very abrupt ending. If you just let students work on an activity till it’s time to go home, you are not only giving them a sudden and abrupt ending to the lesson, you may also come across as disorganized and improvised. The cool down, however, clearly shows students that this is the way you planned for the lesson to end and that you’re ending it like this for a reason. The cool down has its own purpose.
7 effective ways to end a lesson – because those last minutes matter!
What have you learned today?
It goes without saying that you should never end a lesson by introducing something new, just to leave your students hanging till the next class. The best way to end a lesson is to give students some kind of review activity, so that they may see the progress they've made in just one lesson. One of the most common and easiest to implement is simply taking the last 5 minutes of class to ask your students, “What have you learned today?” Notice, here, that you’re not the one telling them what they’ve learned. They may give you a list of new words, or say they learned to speak about what they did in the past or what they will do in the future, etc... Students may pick up something they missed earlier. Also, it's important to speak in functional ways, for example not say they learned to use the “simple present” but rather that they learned to speak about their habits, schedules, and everyday activities.