This website outlines a number of way Vine can be used as an effective communication tool in the classroom (especially useful for PBL based classrooms discussed here!). One of their methods is to create simple how-to videos. In my opinion, this can be used in two ways: first of all, the teacher can create a series of videos that explain or demonstrate a concept. This provides students with alternate instruction they can access from outside the classroom and consists of shorter videos that are more accessbible to students. For example, I feel this could be used effectively to explain a multi-step math problem. Secondly, Vine could be used by students to demonstrate their understanding of a topic. Having students explain concepts in a few seconds allows them to effectively demonstrate their understanding. Additionally, their videos can then be shared with other students who also may require more instruction. This also allows the students to share the role of intruction, an effective method of peer scaffolding. 

Further, assessment using Vine is beneficial as well. Not only does using Vine as assessment promote student engagement and motivation but it also encourages students to create materials that muct be accessible for other. TeacherThought describes Vine as such: "when teachers ask students to create such videos, they are really inviting students to learn, internalize and relay information in a way others can understand. It also serves as an easy means of review days, months or even years down the line. This student-created Vine teaches viewers how to [perform an activity], and is an excellent example of PBL and Vine in action."