In Vygotsky’s theory, these are people who have higher ability level than the learner when it comes to a particular task, process, or concept.
Peer Learning: A teaching strategy where students learn from each other's knowledge and skills.
Mentorship: A relationship in which a more experienced or more knowledgeable person helps to guide a less experienced or less knowledgeable person.
Special skill or knowledge that is acquired by training, study, or practice.