Imagine printing a human heart with the click of a button. Sound impossible? Scientists and doctors are getting closer to transplanting human body parts made from 3-D printers. Read how doctors are using 3-D printers to change lives as you add and subtract fractions. By integrating math and literacy skills, this math reader focuses on STEM topics and makes learning fractions simple, relevant, and fun. Let's Explore Math sidebars, the extensive Problem Solving section, and the clear mathematical charts and diagrams provide numerous opportunities for students to practice what they have learned. The DOK-leveled Math Talk section includes questions that facilitate mathematical discourse and activities that students can respond to at school or home. With intriguing full-color images, the book includes text features such as a glossary, index, captions, and a table of contents to increase understanding and build academic vocabulary. The real-world examples of problem solving allow students to explore STEM concepts in meaningful ways. Practice adding and subtracting fractions with this engaging grade 4 math reader!