The STACK (System for Teaching and Assessment using a Computer algebra Kernel) set of plugins extends your abilities as an instructor to provide feedback to students regarding their work on mathematics and other related subjects.
In brief, the STACK plugin provides a new question type for Quizzes that “concentrates on student-provided answers which are mathematical expressions.” This is a powerful plugin for instructors who want to provide students with high quality feedback based upon the students answers.
The plugin uses Maxima to render and analyze the mathematical expressions created by instructors and students and, one of the most often ‘missing’ pieces of any plugin, STACK is decently documented by its developers for both instructor and student. Back in 2012, the the Transforming Assessment webinar series featured a presentation about how to use STACK, check it out here [direct video link: https://www.youtube.com/watch?v=7aqYgCohLlk]:
