Ask if there were any drills that they did or did not like. Make note of these for the obvious reasons. The second part of the conclusion is announcements. The time and place for the next practice or game. Any special events like picture day or a parade that the team might be participating in.
Some coaches like to hand out announcement slips to each player.
This is especially important if part of the schedule handed out at the beginning of the season has to change for some reason. I typically schedule 5 minutes for the entire Conclusion but seldom use more than 2 or 3. That leaves me a little padding just in case a drill runs over a little bit. The Introduction is where you tell the players what they are going to work on and why. The Warm-up and Activities are where the actual work gets done.