I like this one, also.
Editing symbols for ESL Authors
This looks like a great site for finding editing symbols when providing feedback on writing assignments. Mark the paper with editing symbols, but have students do their own corrections. They will need a table of symbols so that they can interpret the teacher's notations . The site is intended for scientific writing, but symbols are useful for any writing format.
This is site recommended to me by an ESL instructor for teaching listening and speaking. She has her students select a topic of their choice and listen to a TED talk. They listen to the talk a second time and take notes. These are recorded in their listening journal. Occasionally they are asked to present a summary of a TED talk and the class discusses the topic. These activities are good for formative assessment of both listening and speaking skills.