Instruction
The instruction system draws on the idea of presenting educational
lectures that are divided into coherent, semi-independent
subtopics. Existing computer-based education systems have
already been constructed around the assumption that lesson
plans can be composed of tiered modules [29]. These modules
might be adapted from textbooks, coded by teachers, identified
by crowdsourcing using students themselves, or even parsed
automatically using artificial intelligence techniques.
Our prototype instruction component, based on a four-module
lesson plan, offers four minutes of instruction for each module,
leading to a total instructional time of 16 minutes. The lecture
length was informed by studies recommending that optimal
instruction periods last 15–20 minutes [11].