Mohd:
I might suggest that you go to a book store and look at the available material on the subject of 8051 and C. You may find a smaller book that is rather introductory. This would make a good guide as it will have already organized most of the material for you. And you can get each student to buy a copy so they can reference the same material. Heck, with the right book, if it has exercises/projects in it you could almost use it as a text book. You can then supplement this with handouts in the form of the "bible" and other materials like from the Keil site and a single page handout with a link to Host Web Site Here.

I used to do Z80 assembler lannguage classes and the book technigue worked out in a marvelous way. I used to order 30->40 copies and get a wholesale price on them and then sell them to the students at slightly under the retail price (capitalism at work).

Good Luck
Michael Karas

PS. Note that the teacher/instructor always learns far more than the students.
MJK :-)