Lesson objective: Extend understanding that shapes can be equally shared by partitioning a whole and begin to understand that fractions describe the partitioning of a whole.

Students bring prior knowledge of partitioning a whole from 1.G.A.3 and 2.G.A.3. This prior knowledge is extended to partitioning sixths and eighths as students partition gold bars into eighths and sixths and use fraction notation to describe partitioned pieces. A conceptual challenge students may encounter is partitioning into sixths and eighths and understanding the importance of fraction notation.

The concept is developed through work with tape diagrams, which build off students' prior knowledge and sets students up for a transition to number lines in future lessons.

This work helps students deepen their understanding of number because this lesson lays a foundation for understanding why we need fraction notation to describe numbers that result from the partitioning of a whole.

Students engage in Mathematical Practice 6 (Attend to Precision) as they partition one whole into equal shares and compare and constrast partitioned pieces.

**Key vocabulary:**

- eighths
- equal shares
- fourths
- halves
- partition
- sixths
- thirds
- whole