For older students, let them practice their proofreading skills for a purpose. Project Gutenberg has a Distributed Proofreaders program. They need help proofreading their texts and getting them ready for the web:
Description from the site:
“Distributed Proofreaders provides a web-based method to ease the conversion of Public Domain books into e-books. By dividing the workload into individual pages, many volunteers can work on a book at the same time, which significantly speeds up the creation process.
During proofreading, volunteers are presented with a scanned page image and the corresponding OCR text on a single web page. This allows the text to be easily compared to the image, proofread, and sent back to the site.
Proofread as often or as seldom as you like, and as many or as few pages as you like. We encourage people to do ‘a page a day’, but it’s entirely up to you!”
Once all the pages have completed these steps, a post-processor carefully assembles them into an e-book, optionally makes it available to interested parties for ’smooth reading’, and submits it to the Project Gutenberg archive.”
To sign up, go to: http://www.pgdp.net/c/