Provide enough wait-time for students to reflect when responding to inquiries. Provide emotionally supportive environments in the classroom encouraging reevaluation of conclusions. Prompt reviews of the learning situation, what is known, what is not yet known, and what has been learned.
Polyurethane is a fully reacted polymer in which every molecule bonds with another so it is chemically inert, which keeps it from oxidizing or leaching chemicals, theoretically extending tire life. Tires of the future?
Polyurethane is the modern product most often used as varnish, or clear finish, on stained and painted wood surfaces. To achieve the highest level of gloss, and to create the smoothest possible finish, wet sanding each coat of polyurethane is the preferred method.