# Lesson 17

Sums of Tenths and Hundredths

### Lesson Purpose

### Lesson Narrative

Prior to this lesson, students learned to combine tenths and hundredths up to a sum of 1. In this lesson, they extend that work to include larger fractions and continue to build their ability to identify equivalent fractions that are helpful for finding sums.

They also encounter some equations involving unknown addends. While subtracting tenths and hundredths is not an expectation at this point, students can reason about the unknown addends by relying on their understanding of addition, their experience with decomposing a fraction into a sum, and their knowledge of equivalence.

- Engagement

- MLR8

### Learning Goals

Teacher Facing

- Use equivalent fractions to add tenths and hundredths, where the sum is greater than 1.

### Student Facing

- Let’s add more tenths and hundredths.

### Required Materials

Materials to Gather

Materials to Copy

- Fraction Action: Tenths, Hundredths
- Card Sort: Less Than, Equal to, or Greater Than 1

### Required Preparation

Activity 1:

- Create a set of cards from the blackline master for each group of 2-4 students.

Activity 3:

- Create a set of cards from the blackline master for each group of 2.

### Lesson Timeline

Warm-up | 10 min |

Activity 1 | 20 min |

Activity 2 | 15 min |

Activity 3 | 20 min |

Lesson Synthesis | 10 min |

Cool-down | 5 min |

### Teacher Reflection Questions

### Suggested Centers

- Compare (1–5), Stage 6: Add and Subtract Fractions (Addressing)
- Rolling for Fractions (3–5), Stage 2: Multiply a Fraction by a Whole Number (Addressing)
- Compare (1–5), Stage 3: Multiply within 100 (Supporting)

### Print Formatted Materials

Teachers with a valid work email address can click here to register or sign in for free access to Cool Down, Teacher Guide, and PowerPoint materials.

Student Task Statements | docx | |

Lesson Cover Page | docx | |

Cool Down | Log In | |

Teacher Guide | Log In | |

Teacher Presentation Materials | docx | |

Blackline Masters | zip |