8 copies of Sound All Around (Pathfinder). Sounds are all around you. Some can seem very different, but all sounds are a form of mechanical energy. The Explore On Your Own Pioneer and Pathfinder books enable all students to deepen science content knowledge with identical content at two reading levels: Pioneer (grades 2-4) and Pathfinder (grades 4-6). They also provide the opportunity for students to independently apply multiple reading comprehension strategies.