# Dinosaurs

Danny has eighteen plastic dinosaurs. Danny gives nine of his plastic dinosaurs to Lucas. How many plastic dinosaurs does Danny keep for himself? Show all your mathematical thinking.

Instructional

### More Accessible Version

Danny has nine plastic dinosaurs. Danny gives four of his plastic dinosaurs to Lucas. How many plastic dinosaurs does Danny keep for himself? Show all your mathematical thinking.

### More Challenging Version

Danny has twenty-one plastic dinosaurs. Danny gives nine of his plastic dinosaurs to Lucas. Danny gives three of his plastic dinosaurs to Amy. How many plastic dinosaurs does Danny keep for himself? Show all your mathematical thinking.

## Plan

#### Underlying Mathematical Concepts

#### Possible Problem-Solving Strategies

#### Formal Mathematical Language and Symbolic Notation

A student may independently select a printed number line, number chart, ten frames, graph paper, etc. as they work on a task.