Daily Reflection: Evidence and Deadlines

I'm reminded to have sympathy for students that are unorganized or dealing with ADHD/ADD. Having been diagnosed late in life, and remembering what I was like as a high school and college student, I can try and help them to become organized or to find coping mechanisms.

While grading my geometry tests, I am reminded to consider what students consider evidence. Three examples are included below.

Exhibit A

Exhibit B

Exhibit C

Do all three achieve a level of explanation to earn full credit on this problem? Has the teacher established any norms in the classroom to allow Exhibit C to earn full credit on an exam? Mathematicians write proofs with the understanding that their audience will have some foreknowledge of the proof, or at least the mathematics behind it. Anyway, I'm tired and will revisit this again. I need to include a line that asks the students "What evidence do you have for...." This is the essence of proof. I think.