Rocks: Sorting by Color, Texture, and Hardness
Observe, compare, and group rocks by their properties
Rocks: Sorting by Color, Texture, and Hardness
Observe, compare, and group rocks by their properties
Science - Grade 2-3
- 1
You find four rocks. Rock A is red, Rock B is gray, Rock C is red, and Rock D is white. Which rocks belong in the same color group?
Look for rocks that have the same color.
Rock A and Rock C belong in the same color group because both rocks are red. - 2
A rock feels rough and bumpy when you touch it. Which property are you observing: color, texture, or hardness?
You are observing texture because texture describes how something feels, such as rough, smooth, or bumpy. - 3
A student scratches a rock with a fingernail, and the rock gets a scratch mark. Is the rock soft or hard? Explain your answer.
Softer rocks are easier to scratch.
The rock is soft because a fingernail was able to scratch it. - 4
Sort these rocks by texture: smooth black rock, rough gray rock, smooth white rock, rough brown rock. Write the rocks in two groups: smooth and rough.
The smooth group has the smooth black rock and the smooth white rock. The rough group has the rough gray rock and the rough brown rock. - 5
Mia has a tan rock that feels smooth. Liam has a tan rock that feels rough. Are the rocks the same in both color and texture? Explain.
Compare one property at a time.
The rocks are the same color because both are tan, but they do not have the same texture because one is smooth and one is rough. - 6
A rock cannot be scratched by a fingernail, but it can be scratched by a penny. Choose the best hardness group: soft, medium, or hard.
The rock is in the medium hardness group because a fingernail cannot scratch it, but a penny can scratch it. - 7
Look at this sorting rule: Put all dark-colored rocks in Group 1 and all light-colored rocks in Group 2. Where should a black rock go?
Dark colors include black, dark gray, and dark brown.
A black rock should go in Group 1 because black is a dark color. - 8
You have three rocks. Rock A is smooth and white. Rock B is rough and white. Rock C is smooth and gray. Which two rocks match by texture?
Rock A and Rock C match by texture because both rocks are smooth. - 9
A science table has these groups: red rocks, gray rocks, and white rocks. A rock is pink. Which group is it closest to, and why?
Think about which color the rock looks most like.
The pink rock is closest to the red rocks group because pink is a light shade of red. - 10
Which tool is safer for testing a rock's hardness in class: your tongue, a fingernail, or your eye? Explain.
A fingernail is safer for testing hardness because you can gently try to scratch the rock. You should never taste rocks. - 11
A rock is shiny, black, and smooth. Name two properties of the rock from the sentence.
A property is something you can observe about an object.
Two properties of the rock are its black color and its smooth texture. Shiny is also a property that describes how it looks. - 12
Use this rule: Put rocks that can be scratched by a fingernail in the soft group. Put rocks that cannot be scratched by a fingernail in the harder group. Rock A can be scratched. Rock B cannot be scratched. Rock C can be scratched. Which rocks go in the soft group?
Rock A and Rock C go in the soft group because both can be scratched by a fingernail. - 13
A student sorts rocks into groups by size: small, medium, and large. Is this sorting by color, texture, or hardness?
Size tells how big or small something is.
This is not sorting by color, texture, or hardness. The student is sorting by size. - 14
Four rocks are on a tray. Two are rough and two are smooth. Write one question you could ask to sort them by hardness.
One good question is, can the rock be scratched by a fingernail? This question helps sort the rocks by hardness. - 15
Nora wants to sort her rocks fairly. She first sorts by color, then she sorts the same rocks by texture. Why can the same rocks be sorted in more than one way?
One rock can have a color, a feel, and a hardness.
The same rocks can be sorted in more than one way because each rock has many properties, such as color, texture, and hardness.