This review of the literature gives an in-depth overview of inferencing, explaining what it is, why it's important, and how we can effectively teach it. This is a great place to start. (Added by BloomBoard Spark)
There are several useful lesson plans here, based on "reading between the lines," character actions, pictures and more. These are created for 3rd grade, but can be easily adapted for all levels in lower and upper elementary. (Added by BloomBoard Spark)
This resource correlates inferencing strategies to Barrett's Taxonomy of Reading comprehension, then gives multiple resources and suggestions for mastering each one. The activities cover a very wide range of grade levels and would be useful for differentiation.
This presentation defines inferencing as a reader and as a writer. The presentation offers multiple resources including books and videos to help teach inference skills in primary, secondary, middle, and high school students.