Student's prior knowledge

Student's background knowledge is so imperative when asking them to complete a cumulative task. How can we, the teachers, expect students to write about a topic that they do not clearly understand? How can we assume that the students will pick up on the nuances in their reading (i.e. novel) without first modelling it through a "read out loud". I remember taking a first year English course at a university, and I thought I knew everything about writing an essay, but little did I know I knew nothing when my professor went through the structure/process of writing through a minute step-by-step explanation, both verbally and visually, and with repetition. That course was probably the most valuable course that I've ever paid for. Like what the professor did for us, teachers really need to take the time to explain important ideas/concepts with detail and repetition.

Thinking back, asking students to write an essay on a topic based on their reading seems vacuous. As teachers, we need to scaffold their understanding on the topic by bringing-in other texts other than the primary document, and allow students to explore the topic from various medium, text, and angles.

I get it now.