Toy designed for older audiences, such as teenagers or adults, demonstrate advanced concepts. Newton's cradle, a desk toy designed by Simon Prebble, demonstrates the conservation of momentum and energy. Not all toys are appropriate for all ages of children. Even some toys which are marketed for a specific age range can even harm the development of children in that range. "Age compression" is a toy industry term that describes the modern trend of children moving through play stages faster than they did in the past. Children have a desire to progress to more complex toys at a faster pace, girls in
Office of Energy Efficiency and Renewable Energy its changing scope, including the Office of Conservation and Solar Applications (CSA), the Office of Conservation and Solar Energy (CSE), and the Office of Conservation and Renewable Energy (CRE). The agency gained its current name, the Office of Energy Efficiency and Renewable Energy, in 1993. The EERE's mission is defined as "to create and sustain American leadership in the transition to a global clean energy economy." The office also develops initiatives to advance specific technologies. The Office of EERE is led by the Assistant Secretary of Energy Efficiency and Renewable Energy, who is appointed by the president and confirmed by