There is a TeX filter for Moodle (http://docs.moodle.org/en/TeX_filter)

that allows students to enter mathematical equations in any text editor.

The attached document shows the syntax students can use to represent mathematical symbols. Since the text editor is used throughout Moodle, this means that instructors have options about how to ask students to show their work.

-- Quiz: Instructors can create essay questions that require students to show their work. Each essay question is individually graded, so instructors can give partial credit if they make each question worth more than one point.

-- Forum: Instructors can create a discussion forum where students show their work. I would recommend that the instructor only allow replies and make each question a separate forum topic (thread). That way the answers to each question are grouped, making it easier to grade. Forums allow cumulative grading, so the instructor can grade each question individually (again, partial credit is possible). It is also possible to create a forum (the Q&A forum, I think) that requires students to answer each question before being able to see other students' responses.

-- Assignment: Instructors can create an online text assignment that allows them to provide in-line feedback to students. The instructor could lump all the questions into one assignment or make a separate assignment for each question.

-- Wiki: Instructors can create student wikis--where each student gets his or her own wiki. The student could make a different wiki page for each question. It is possible to allow students to see each other's work or to keep them separate.

Using Moodle for communication only, instructors can use forums or assignments to have students upload files that they create offline.