# Investigations Blog

## Q&A: Mathematical Vocabulary in Investigations 3

Question: How does Investigations approach the teaching and learning of mathematical vocabulary? Answer: In Investigations 3, mathematical vocabulary is introduced as a natural part of the conversation during activities and discussions, along-side studentsâ€™ own words. Rather than memorizing the definitions of new terms, students come to understand such words as factor or area or symmetry as they investigate and discuss new concepts. Hearing new mathematical terms used regularly, and having...

read more## Q&A: The Definition of a Trapezoid

Question:Â Why did you decide to use the exclusive definition of a trapezoid? As the question suggests, there is more than one definition of a trapezoid. Mathematicians define trapezoids in one of two ways: Using the inclusive definition, all parallelograms (which include rectangles, squares, and rhombuses) are trapezoids. Using the exclusive definition, they are not. In determining which definition to use, we thought about a couple of things: Most elementary textbooks use the exclusive...

read more