Make folks aware of your attentiveness to the finishing the lesson on time. Its super easy and it makes people feel comfortable. Try these simple phrases.
At the start, say something like “We will be done in 45 minutes at 8:00 tonight”.
In the middle, say things like “We gotta keep moving”.
Near the end, say something like “We have 6 minutes to wrap up this lesson. We can do it!”
Afterwards say something lighthearted like, “We ran our typical 2 minutes over.”
All of the above shows people you really care about finishing on time. Trust me, they will appreciate it!