Download Second Grade – Lesson Overview Pebbles, Sand, and Silt Students

Second Grade – Lesson Overview
Pebbles, Sand, and Silt
Students Learn:
Rocks have a variety of
properties. When rocks rub
together, some (softer) rocks
may be chipped or scratched,
or make rock dust.
Rocks have a variety of
properties. When rocks are
washed in water, the colors or
sparkling qualities are
enhanced.
Rocks can be sorted by their
properties.
Investigations:
Investigation 1,
Part 1: Three
Rocks
Students Do:
Students investigate and sort a set
of six rocks. They gather
information about the rocks by
matching the rock samples and
rubbing them together.
Investigation 1, Students wash their samples to see
Part 2:
how the rocks change when they
Washing Three are wet and what happens to the
Rocks
wash water.
Investigation 1, Students are introduced to river
Part 3: First
rocks. They listen to the story
Sorting
“Peter and the Rocks” and use
ideas from the story and Part 2 to
sort their river rocks.
Rocks can be sorted by their
Investigation 1, Students use sorting mats to play
properties.
Part 4: Sorting sorting games with the river rocks.
games.
Rocks are all around us. Rocks Investigation1, Students start to organize a
are the solid material of the
Part 5: Start a classroom rock collection.
Earth.
Rock Collection
Screens can be used to sort the Investigation 2, Students separate a river rock
sizes of earth materials. Rock
Part 1:
mixture, using a set of three
sizes include sand, small
Screening River screens. At the end of the
gravel, large gravel, small
Rocks.
separation, students discover they
pebbles, and large pebbles.
have five sizes of materials: large
pebbles, small pebbles, large
gravel, small gravel, and sand.
Rocks can be categorized
Investigation 2, Students activities reinforce the
visually by size. Rock sizes
Part 2: River
idea of grouping rocks based on
include sand, small gravel,
Rocks by Size
size.
large gravel, small pebbles,
and large pebbles. Rocks larger
than pebbles are cobbles.
Rocks larger than cobbles are
boulders.
Sand often contains smaller
Investigation 2, Students take a close look at sand
particles, called silt. Water
Part 3: Sand
and separate sand particles from
can be used to sort the sizes of and Silt
silt particles, which are smaller
earth materials.
than sand, by mixing the sand with
water and allowing the particles to
Clay particles are very small,
even smaller than silt.
Earth materials are natural
resources. The properties of
different earth materials make
each suitable for specific uses.
Earth materials are commonly
used in the construction of
buildings and streets.
The properties of different
earth materials make each
suitable for specific uses.
The properties of different
earth materials make each
suitable for specific uses.
Earth materials are used to
make jewelry and sculptures.
The properties of different
earth materials make each
suitable for specific uses.
The properties of different
earth materials make each
suitable for specific uses.
Simple bricks are made by
combining clay soil with plant
material.
Soil is a mixture of earth
materials. Humus is decayed
material from plants and
animals. The ingredients of
soil can be observed by mixing
soil with water, shaking it, and
letting it settle.
Soils vary from place to place.
settle. They observe that the sand
settles to the bottom and the silt
forms a layer on top of the sand.
Investigation 2, Students investigate the properties
Part 4:
of very small rock particles, clay.
Exploring Clay
Investigation 3, Students learn how people use
Part 1: Rocks
rocks as natural resources to
and Use
construct objects and to make
useful materials. They start by
looking outside the school building
for places where earth materials
can be found naturally or as
building materials.
Investigation 3, Students observe sandpaper and
Part 2: Looking compare it to sand. They make
at Sandpaper
and compare rubbings of three
grades of sandpaper.
Investigation 3, Students mix sand with cornstarch
Part 3: Sand
matrix to make durable sand
Sculptures
sculptures.
Investigation 3, Students use clay to make beads or
Part 4: Clay
something decorative, which they
Beads
paint and keep as a memento of
their investigation of clay.
Investigation 3, Students make adobe clay bricks
Part 5: Making with a mixture of clay soil, dry
Bricks
grass or weeds, and water. After
the bricks dry, the can be used to
build a class wall.
Investigation 4, Students put together and take
Part 1:
apart soils. They are introduced to
Homemade Soil humus, an important soil
ingredient. They mix together
homemade soil containing sand,
gravel, pebbles, and humus. They
shake some of the soil on a paper
plate and observe what happens.
They use screens to separate the
homemade soil. They shake soil
and water together in a vial and
draw their observations.
Investigation 4, Students go on a schoolyard field
Soils have properties of color
and texture. Different soils
differ in their ability to support
plants.
Soils can be composed of
humus and different amounts
and sizes of rocks.
Part 2:
Soil Search
trip to collect soil samples. They
try to find soil in as many places as
possible: next to sidewalks, near
trees, and in landscaped area.
Investigation 4, Students study their schoolyard soil
Part 3:
samples. They shake some of the
Studying Local soil with water in vials and draw
Soil
the results. They compare the
vials in drawings of their
schoolyard samples with the vials
and drawings of the homemade
soil.