I would like to get some feed back regarding something that the school i teach at has asked/told me I must do.

I have been told that I must create for them a new English classroom text book for grade 1 to 3. After nearly two days bashing my head against the wall trying to get more info out of them, they finally told me that they want them just like the ones we already use but that they want me to re-write, re-word it. This sounds absolutely rediculous to me! What is the point of doing it as the text books we use now are written by native English speakers and have no "faulty" English, spelling mistakes etc. So why tell me to re-word it? The only answer I can get out of them is that I have to do it and it will make the school principal happy. 

Now.. I have lived and worked in China for over 5 years now and have yet to be asked to do something that is so pointless and time wasting. The Only thought I can come up with as to why they are telling me to do this is so next semester they will have no need to buy and text books as all they will need to do is print out a heap of copies of the ones I have re-worded or "made"  for them.

Also,in my contract there is nothing about doing this kind of work for them.

What are peoples opinions on this???