I would suggest volunteer at existing clubs.
I go to two junior clubs, age ranges are from 6 to 16 and one weekend is more technical based, the other is more fun based. It’s good to get both angles and see what works for which children and age groups.
In general, younger children are harder to teach as they are distracted easier or can give up easier (say 9 and below ages).
I don’t know how long you have with the students, but do some sort of warm up, something technical like grip or a shot practice, and do games and maybe a bit of competition.
Half court singles is great for the older groups. Play for up to 3 minutes, winners move up a court. Keep track of the scores of each game and ask them at the end how they did. Play 4-6 rounds. It should help them with accuracy, movement and tactics.