The world of hackers is complex. White hat hackers are hired to protect private information. But there are also black hat hackers who want to create chaos. Develop your expertise with expressions as you explore the secret world of computer hackers! Packed with factual information and high-interest content, this nonfiction math book uses real-world examples of problem solving to build students' math and reading skills. Let's Explore Math sidebars feature math questions that challenge students to develop their math skills. A problem-solving section at the end of the book prompts students to reflect and apply what they've learned. Demystify math with this leveled book that makes learning math fun and accessible for kids ages 10-12 and appeals to reluctant readers.