A complete unit with direct instruction to the student, ample practice problems and word problems. Common Core aligned. Great for independent practice/homework.
The unit Fractions, Grade 4 deals with mixed numbers, adding and subtracting like fractions and mixed numbers with like fractional parts (the denominators are the same), equivalent fractions, comparing fractions, and multiplying a fraction by a whole number.
The topics in this book are studied with the help of visual models in order to emphasize the concepts.
These topics are important because they are the basis for understanding decimal numbers -- as I'm sure you know, decimals are just another way of writing fractions with denominators of 10, 100, 1,000 etc.