Students become mathematical adventurers in these challenging and engaging activities designed to deepen and extend their understanding of concepts from the Common Core State Standards in Mathematics. The investigations in this book stretch students' mathematical imaginations to their limits as they investigate the numeration systems of creatures from another planet, create and solve stories and problems with extreme numbers, use place value to design their own new divisibility strategies, and play with a strange kind of number line specially designed to multiply numbers without a calculator. Each activity comes with detailed support for classroom implementation including learning goals, discussion guides, detailed solutions, and suggestions for extending the investigation. There is also a free supplemental e-book offering strategies for motivation, assessment, parent communication, and suggestions for using the materials in different learning environments.