Science in Year 3

Date: 9th Oct 2024 @ 3:47pm

How are rocks made?

This half term we are studying rocks.  This ties in very nicely with our History topic about The Stone Age. 

We discovered that rocks are made underground in the Earth’s core and come to the surface through volcanoes.

Vocabulary Alert: Molten rock is hot liquid before it cools and solidifies.  Year 3 has also been learning about the terms ‘metamorphic’, ‘sedimentary’ and ‘igneous’.

The children thought:

“When you add an acid to chalk it fizzes and made bubbles.”

“The acid reacted with the calcium carbonate to make carbon dioxide or CO₂.”

“Igneous rocks come from volcanoes like granite, pumice and obsidian.”

“Some rocks were formed underground like mudstone turning into slate.”

“A sedimentary rock, like limestone, is made of layers of mud, sand and dead animals and plants.”

“A metamorphic rock, like marble, is hard and strong.”  

We have compared the different rocks as well as learning some of their names and properties.

Here are some observations and knowledge that the class have already shared with their friends.

We concluded the rocks are different in many ways.

• texture (rough and smooth)
• colour e.g. brown, red, white, grey
• weight (heavy and light)
• appearance (pattern, plain, crystals)
• size and shape

We also tested which rocks were chalk or limestone by adding citric acid (lemon juice) and acetic acid (vinegar) to rock samples.  This was a fantastic investigation and the children loved making their chalk fizz.

Next, we are asking ourselves ‘What is soil?’ and ‘How are fossils made?’

Well done super scientists!