Learn · Illustrative Mathematics K–5 · Grade 4 · Unit 9
Short lessons you can play with, looking back at the year. Add, subtract, and multiply fractions, work the standard algorithms and partial quotients, solve comparison problems, and estimate, then check yourself.
Four short chapters review the year, following the unit’s lessons in order. Each step shows one idea with something to tap or move, then a quick check. A wrong answer names the likely mistake and gives one more try. Progress is saved on this device.
Fractions have like denominators. Whole numbers go up to 4 digits, multiplied by 1 digit or 2 digits by 2 digits, and divided by 1 digit. Estimates round to the nearest ten, hundred, or thousand.
Partial quotients: dividing in easy chunks and adding them up. Estimate: an answer that’s about right, found with friendly numbers. Times as many: a comparison by multiplying.
Create Word Problems (Lesson 9), Which One Doesn’t Belong? (Lesson 11), and Number Talk (Lesson 12) are open-ended lessons, best done with others. Practice it all in Year-End Fair, the game for this unit.