With time travel and mysteries that need solving, the Galactic Academy of Science (G.A.S.) series instructs readers on how to think like scientists. Under the guidance of a Dude or Dudette from the future, the middle school characters are faced with treacherous, present-day crimes that require a historical knowledge of science in order to be solved. From investigating problems to analyzing data and constructing explanations and solutions, this series blends elements of sci-fi with educational methods that distill the key thinking habits of scientists and engineers. Medical science combines with mystery in this G.A.S. adventure about concussions Is the awkward stranger taking bribes to throw games? When Clinton hits his head in the championship soccer game, the stranger gets him benched, and Clinton's team loses. Determined to nail the bribe-taker, Clinton and Mae take on a new G.A.S. mission--a journey across three continents and 4,000 years to learn about concussion and the brain.