2nd Grade Investigates Volcanic Rocks

2nd graders have begun their unit on rocks by observing the properties of three different igneous rocks: basalt, tuff and scoria. They described how the rocks felt, looked and even smelled! Then, we rubbed two of the same rocks together to see what happens.  The scoria and tuff both make rock dust while the basalt is such a hard rock that they just make scratch marks.

The next investigation had us putting the rocks, one type at a time, into a cup of water. What would happen? The gray basalt rock looked darker.  The red scoria had bubbles rise from it and it turned lighter in color.  The white tuff turned orange and even purple! There was also a steady stream of very small bubbles coming out of the tuff.  We also noticed that the rock dust made the water look "dirty".     

2nd Graders Rock!

Over the past few weeks, 2nd grade has been making and recording observations about three igneous rocks: scoria, basalt and tuff. They have described how it looks, feels and even smells as well as what happens to the rocks when they are rubbed together over black paper.

Using a double T chart to help organize observations.

The gray rock, basalt, is smooth.

The scoria, reddish rock, is rough.

The tuff rock leaves a little white on my fingers.

Rubbing the two scoria together makes rock dust!

The tuff is so soft it can even flake off onto the paper.

The gray rock makes white marks on the other grey rock, but
doesn't make dust.

Recording observations in our science notebooks
helps us remember.

2nd graders work together and share information just
like scientists do.

Next they put the rocks, one type at a time, into water and wrote down our observations.  We were so surprised that something happened to each type of rock, but it was important to be patient and watch!

The basalt rock turned darker in the water.

The scoria rock turned darker or brighter depending on the
original color.

Some of the tuff changed colors - orange, cream
and even purple.

The water looks a little dusty.

There are bubbles!

The rocks are smoother when they are wet.

There are tiny bubbles coming from the rock.

It's so cool to see the rocks change colors.

The tuff looks all crackly.