The students, the teacher, and I (teacher associate) were talking about density today.

The village "was worried about traffic and density," she said.

This would also be a great time to tell them about density.

And some residents have expressed reservations about density of development.

"We still have many unanswered questions, mostly about density, that were not satisfactorily addressed at the meeting."

She shared the most recent data about the blade's size and density, its velocity and point of impact.

I am in 4th grade and my science teacher just taught us about density.

In this case, I would say it makes more sense to talk about average density.

It's something about density, the way it holds its branches.

For example: by building and launching a hot air balloon we learn about weight, density and pressure.