Final answer:
In the context of Vygotsky's Zone of Proximal Development, Professor Lively uses peer collaboration to introduce purposeful teaching in a testing situation to assess what children can achieve with social support.
Step-by-step explanation:
Professor Lively, while adhering to Vygotsky's Zone of Proximal Development, employs a teaching method that involves introducing purposeful teaching within a testing environment to discover what children can achieve with social support. This method falls under the category of peer collaboration, which is designed to maximize the learning potential of students by working together and supporting each other's learning processes.