Free Middle School Chemistry Curriculum
Middle School Chemistry, a free science curriculum from the American Chemical Society, has “inquiry-based lesson plans that cover basic chemistry concepts along with the process of scientific investigation.” Each chapter may be downloaded (as a .pdf file) along with lesson plans and teacher manuals. All of the content is free!
The chemistry course could be completed in 8-10 weeks, depending on the time available. Each lesson takes about 45 minutes.
Look at the free middle school chemistry program here.