What you are doing right and the others aren't is two fold.

First of all, you have a progressive series. A person can actually start from the beginning and work their way up to a conversational level. All the words are accounted for. You remind people of what is new and what has been covered already. You remind them in Chinese and use English sparingly.

This is the way that it should be done. After the initial stages, a language should be taught in the target language as much as possible.

The second thing – Lessons are introduced in Chinese.

I am just learning Chinese as a hobby, really. In my job (I teach and research Biochemistry at Sydney University) I come across a lot of Chinese people (both fellow scientists and students) and, although they all speak perfect English, it is a good ice-breaker and much appreciated if I have a go with my Mandarin! However, some of my more cynical colleagues think I'm only learning so that I can tell what the students in the front row of my lecture are saying about my classes :-)

I have been learning for about 6 months... I really like the way your course is 'progressive'...