Book

The short answer is No, because any one who is determined could simply do screenshots of the  material anyway, even turning it into nicely printable pdfs. What you can do I suppose is instead of uploading files such as Word processed documents, you can put the reading material in as a Page Then they can't easily download it and they are forced to think of other ways such as screenshots.  But in short, if your material is so important you do not want them to download or print it, then it should not be on the internet