BK in our class doesn't refer to the fast food chain. Instead, it is a part of our reading with code, a note taking short hand that allows us to quickly mark and identify questions(?), connections(c), background knowledge(bk), and new learning(!). Using this code not only tracks our thinking but also gives purpose and organization when tackling non fiction texts.
A more specific goal has been connecting our background knowledge to new learning, sometimes revising or building off of what we thought we knew. I gave the analogy of building bricks to construct a castle on a topic. Depending on the topic, we might have a lot of bricks (background knowledge) on something or very few to begin with, however, through non fiction exploration, we can add to our understanding and become experts as we build taller and stronger with our new learning.
Moving forward, I am encouraging them to mark up the margins with thoughts, reactions, questions, using our code to deepen understanding! If we can't write in the book, I love keeping sticky notes ready as I read to quickly jot down interesting new things I learn or am excited about sharing.