Interactive reading is SO beneficial to readers. As adult fluent readers, we perform these strategies mentally all the time. Getting our readers to stop and think about them as they read is a steppingstone to having them achieve automaticity with these skills, which will ultimately help improve reading comprehension, retention, and enjoyment.
Trying to figure out how to show kids the value of using Post It notes while reading interactively and strategically? Try handing out these instructions. You can assign a score by making Post Its worth 5 points (or 10) and giving them credit for what their Post Its contain. You can ask for a variety of Post Its for homework (e.g., "Read for 30 minutes and do any two strategy Post Its for tomorrow) or collect during a silent reading class. You can also do a long write (see my Grade 8 Reading Workshop Long Write document) as a culminating activity and assessment piece at the end of a week or every week of the marking period.