Math becomes increasingly complex in fourth grade.

For many students, fourth grade marks the transition from basic arithmetic to more complex mathematical reasoning. The Common Core Standards, which have been adopted by 45 states, emphasize three critical skills students learn in fourth grade math: understanding that it's possible to analyze geometric shapes, multiplying multidigit numbers, and developing a basic understanding of fraction equivalence. Most fourth-grade math skills are designed to help students achieve these broad learning goals.

### Multiplication and Division

Fourth graders begin multiplying larger numbers -- including two and three digit numbers -- as well as multiplying three numbers at once. Students will also begin to learn the relationship between multiplication and division, and master simple division problems. As students acquire the basics, they'll progress to division with a remainder and long division.

### Fractions and Decimals

Fourth graders learn the relationship between fractions and decimals and master converting one to the other. They'll begin to recognize equivalent fractions, learn how to compare two fractions, and master reducing fractions. They may also be required to develop fractions based on graphic representations, or turn fractions into illustrations. Students will also learn how to multiply a whole number by a fraction.

### Geometry

Fourth grade math is designed to give students the basic skills they need to progress to more complex geometry in fifth grade and middle school. They will learn how to draw lines and angles and will begin to understand that angles determine shape. As part of their preparation for geometry, students will also learn to use measurement tools and may learn basic geometric formulas such as calculating the area of a square.

### Mathematical Reasoning

Fourth grade marks a shift toward a stronger emphasis on mathematical reasoning. Students will learn to work with numbers to the millionth place value, and learn tools for estimating solutions to problems. They'll also be introduced to the basics of probability and statistics and will learn to analyze simple graphs and to gather information to determine probability. Students may also be required to develop simple proofs and explain why a mathematical concept is true. For example, a child might be required to "prove" the answer to a multiplication problem using division or by explaining the process of multiplication.