This is almost certainly a matter of "house style" and not strictly of grammar. My own personal style has two forms where the list items contain more than a very simple term. One is where the list is preceded by a sentence fragment and is constructed such that each item, when appended to the sentence fragment comprises a grammatically correct sentence. For example:
Dogs are:
- commonly kept as household pets
- often referred to as being the "best friends" of man
- a pain in the neck when they're puppies and are prone to peeing on the floor
The other type of list is where each item stands on its own as a syntactically correct sentence. For example:
Dogs have various characteristics:
- They are commonly kept as household pets
- They are often referred to as being the "best friends" of man
- They can be a pain in the neck when they're puppies and are prone to peeing on the floor
(Note: in neither do I end items with a period, but again that's a stylistic thing rather than a grammatical/syntactical one.)
The biggest frustration I find is where people mix up those and other forms. Consistency is probably the most important thing here.
One other comment, about your particular example. In fact, both could fit into my second style if everyone concerned knows who the professor is, is on familiar terms with him/her, and in fact refers to him as "Professor" -- i.e. in the way kids might refer to their father as "Daddy". For example:
Here's a snippet of the schedule for an upper class English kid whose father has been summoned to a meeting about said kid's bad behaviour:
First, the kid's version:
- Teacher expects me in her office by 2:55pm
- Father is coming around 3:00 PM
And the teacher's version:
- Student arrives in my office by 2:55pm
- The father is coming around 3:00pm