Exploring River Rocks!

Second grade has been busy learning about properties and sizes of rocks.  They sorted river rocks by color, size, texture, luster and shape.

Sorting by color.

Sorting by color can be hard because each rock can have
so many colors in it!

We put the river rocks in water to see if it changed the way we
would sort our rocks.

Looking at a river rocks mixture.

So many different sizes and colors!

The rock mixture was harder to sort by hand, so we used three different sized mesh screens to help!

The medium sized rocks stay on the medium screen.

The large rocks stay on the large screen.

Four different sized rocks...all sorted!

Trying all three screens together.  As long as they
are stacked small, medium and large,
they still sort the rocks!

Writing down observations.

Some of the bigger rocks can slide through, depending on the
shape of the rock.

Rock get their name from what they are made of and by what size they are.
The river rock mixture was made up of pebbles, gravel and sand.

2nd Grade Screens River Rocks!

Second graders have been investigating what happens when screens are used with a river rock mixture!

Right away we noticed that the rock mixture
has rocks of different sizes.

We also noticed that the rocks are different
colors.

The classes explored with three different sized screens and thought about what happened to the rock mixture when they used the screens.

Some of the rocks can be pushed through the screen.

Writing down observations.

One rock is stuck in the screen!

Then they experimented with the screens.  What happens with the rock mixture when it is poured through all three screens at the same time?

Most of us came to the same conclusion - The big rocks didn't go through any of the screens, the medium rocks stayed on the medium screen, the small rocks stayed on top of the small screen and the smallest rocks went through all four screens!

2nd Grade Sorts River Rocks!

2nd graders have been investigating river rocks!  They began by observing and sorting the rocks by properties: color, shape, size, luster and texture. We were surprised at how most of the rocks were more than one color and many of them had patterns. 

We discovered that most of the river rocks were smooth, sparkly and had more than one color.

The next class we sorted the river rocks by properties again and put each sorted group into water to see if the rocks would change in any way.

We were so surprised that the dull rocks turned shiny and the shiny rocks turned dull when they were put in water.  And the river rocks changed color when they were wet. Some even turned green!

Screening River Rocks in 2nd Grade!

We have begun looking at a river rock mixture.  These rocks are found at the river bank - where the river and land meet.  

After looking at the mixture, we noticed there were different sizes and colors of rocks.  We even found small pieces of mica and pyrite (fool's gold) in the mixture.

After learning that some people use this mixture to make roads, sidewalks and other structures, we experimented with three different sized mesh screens to see what happened when the mixture was poured over them.

The large rocks stay on the large screen,
the medium sized rocks stay on the medium screen,
the small rocks stay on the small screen,
and the teeny rocks fall through all three screens!

The mixture that fell through the screen is more colorful
than the rocks that stayed on the screen.

The sand is so soft.

We tried putting the mixture through all three screens at once.
It worked!

Sometimes you have to shake the screen so the smaller rocks
can get through.