Overview8 copies of Scope This Out (Pioneer). Telescopes have been used for about 400 years. They let people see things that are far away, but the story of telescopes really started with eyeglasses. 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.