Whilst I am not a qualified teacher, I have had experience teaching new sailors their jobs when I was in the Navy. (got a couple of teaching certificates out of it). The first thing is patience and more patience. This is completely new learning to them, just think of how you would like to be starting out learning Chinese for example. When I was teaching I had "it takes patience to get a good student" written on my desk. I would read that before I left my office to begin any lessons. It help to put me in the right frame of mind and I could then concentrate on what I was trying to achieve that lesson. Secondly only go as fast as the slowest learner. But do not do this continuously as others will get bored and not wish to continue with the course. I would think that for a younger audience you would want a book that has big pictures say for example a star with the word in English as large as possible. That way they can picture the star and the word in Chinese and then you tell them the English word and get them to repeat it a couple of times. I would suggest very basic sentences to begin with and then expand from there. This would apply to all age groups. Also it is important at the beginning of each new session to review the last lesson. This gives the memory a jolt, people start to feel that they have achieved something by remembering words from the last lesson and then the new lesson can begin. Make sure that each lesson flows from one to the other in some form. Taking the star example above, you may want to focus all the learning on heavenly bodies for a couple of lessons IE. sun, stars, moon etc. The worst thing about trying to learn something is when you jump from one topic to another that have no relation in the type of learning that has been studied last lesson. For sentence structure each word written onto magnetic strips or whatever type of resource you have place them individually onto a board and then you can move the words around to give different meanings to each sentence.
All the best, just my thoughts only.