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Lesson 2: Challenging Substances
AUTHOR'S NAME: Alexandra Barr
TECHNOLOGY LESSON: No
DATE OF LESSON: Day 4
LENGTH OF LESSON: 55 minutes
NAME OF COURSE: 2nd Grade
Science
SOURCE
OF THE LESSON:
- Beals, K. &
Willard, C. (2007). Matter: Solids, Liquids, & Gases GEMS Teacher’s Guide for Grades 1-3.
University of California at Berkeley, p. 45-57.
TEKS ADDRESSED:
§112.4.
Science, Grade 2
2.2 (D) gather
information using
simple equipment and tools to extend the senses.
2.2 (E) construct
reasonable
explanations and draw conclusions using information and prior knowledge.
2.5 (A) classify
and sequence
organisms, objects, and events based on properties and patterns.
2.7 (A) observe, measure,
record, analyze, predict, and illustrate changes in size, mass,
temperature, color, position, quantity, sound, and movement.
CONCEPT STATEMENT:
- Solids and liquids have very
distinct
properties. Sometimes a material can be
questionable. These materials can be
classified as colloids. They share the
same properties as a solid, and a liquid. But,
there are materials that can look like a liquid, and
remain a
solid-not a colloid. The same can be
true about a liquid looking like a solid.
- It is important to understand
where certain
substances are classified, so that real life experiences can be
scientifically
based on sound reasoning.
PERFORMANCE
OBJECTIVES:
Students will be able to. . .
- Define and apply the properties of solids and liquids.
- Discuss why questionable materials such as sand and shaving cream are categorized where they are.
- Explain
why they reached any/all conclusions
- Collect
and measure substances
- Work
well in a group, and follow all directions.
RESOURCES:
- Per Class
- Solids and Liquids
display from previous sessions
- Rock and a few other
solid and liquid items from previous sessions
- A small amount of
baking soda
- 1 clear plastic cup
- Per Student
- Journal from previous
sessions
- One copy of the Solid or Liquid? student sheet (page 54)
- For pre-writers:
sticky notes instead of a student sheet
- Pencils
- For the toothpaste,
shaving cream, and sand stations
- 4 cafeteria trays
- 4 trash containers
- about a cup of shaving
cream
- about ½ tube
toothpaste
- toothpicks
- about a cup of sand
- 6 wide-mouth plastic
cups
- 8 hand magnifying
lenses OR handhels microscopes
- 4 dishtubs for washing
hands
- paper towels
- water
- 2 dustpans and brooms
for cleaning up
- (optional) dissecting microscopes
- For two Glook Stations
- A 1-teaspoon measuring
spoon
- A 1-tablespoon
measuring spoon
- 2 sealable plastic
bags or other airtight containers
- 8 tablespoons of white
glue
- 8 tablespoons of water
- 2 cups
- 1 stirrer
- 4 teaspoons of Borax
powder (Sodium Tetreborate, used in laundering and as a
household cleaner)
- 1 cup of warm water
SAFETY CONSIDERATIONS:
The
students will be working with a variety of materials, most of which
will be
questionable (such as shaving cream and Oobleck). These
materials aren’t harmful externally,
but they are hazardous when ingested. The
students will be instructed not to eat any of the
materials, as well
as not to put the material anywhere near their faces. They will be instructed to wash their hands
as soon as the experiment is completed.
SUPPLEMENTARY
MATERIALS,
HANDOUTS:
- Solid or Liquid? – 1
handout for each student (p. 54)
- Journals from previous
sessions
Specific
Considerations for each of the 5Es:
Engagement |
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Time: 10 |
What the Teacher Will
Do |
Probing Questions |
Student Responses
Potential
Misconceptions |
Introduce hand signs
for the words solid and liquid. |
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Hold up different
substances. |
Is this a solid or a
liquid? Show me. |
Solid or liquid sign. |
Hold up a liquid
substance in its container. |
Is everything in my
hand a solid or a liquid? Show me. |
Solid sign, liquid
sign or both.
If both are shown, ask
students why both are possible. |
Allow students to
justify all answers. |
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Bring attention to
solid and liquid display. |
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Briefly discuss the
substances up on the board. |
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Review substances
using hand signs. |
Can you show me what
each of these materials is using your hand signs? |
Solid or liquid sign. |
Exploration |
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Time: 20 |
What the Teacher Will
Do |
Probing Questions |
Student Responses
Potential
Misconceptions |
Explain to the
students that they will be working with “questionable” materials. |
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Pair the children up,
and allow them to freely explore the four different materials at the
different centers. |
What do you think
these different materials are? Why? |
Solid or liquid.
They could be both. |
Make sure the children
understand that they are not collecting samples of any of the materials. |
Why don’t we
brainstorm about these materials? |
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Pass out the Solids or
Liquids? journal page. |
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Demonstrate the
exploration of each material at each station. |
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Have the children
re-evaluate the materials at each station, then circle Solid, Liquid or
Not Sure on the Solids or Liquids? Journal sheet. Then
have them explain why. |
Why do you think that
substance is a solid/liquid?
What about it makes
you not sure? |
Takes up space.
Holds shape of
container.
Color. |
Have the children
explore each material, then sit down at their desks. |
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Explanation |
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Time: 10 |
What the Teacher Will
Do |
Probing Questions |
Student Responses
Potential
Misconceptions |
After the students
have gathered at their desks, bring one of the questionable substances
to the front of class. |
Is this a solid or a
liquid?
Why do you think it is solid?
Why do you think it is liquid? |
Solid or liquid are
both acceptable answers.
It holds its shape, it looks solid
you can put your hand through it. |
Have the students take
a vote on the questionable material. |
Who thinks this is a
solid?
Who thinks this is a
liquid? |
Accept any answer |
Explain to the
students that Glook, toothpaste and shaving cream are all solids and
liquids. They are classified as colloids. |
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Bring up the material
of sand. |
Is sand a solid? Is
sand a liquid? Can you explain why? |
Accept all answers. |
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What did sand look
like in the magnifying class? |
Rocky. Like broken up
shells. |
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What is the sand made
of? |
Rocks and broken
shells. |
Ask the children to
recall what was decided about the chalk. |
Was the chalk a solid
or a liquid? |
Yes/No |
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Even after we broke it
up into smaller pieces? |
Yes/No |
Remind children that a
solid can be any size, as long as it holds its shape. |
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Elaboration |
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Time: 10 |
What the Teacher Will
Do |
Probing Questions |
Student Responses
Potential
Misconceptions |
Show the children an
even smaller solid, such as baking soda or powder. |
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Have the children
problem solve through the smaller powders, to arrive at the conclusion
of solid. |
I think this is a
liquid. Can you tell me why this might be correct? |
Holds shape of its
container.
Can be poured.
You can stick your
finger through it. |
Help children
understand what a solid’s properties are, even if they’re questionable
solids. |
Can you tell me why
this might be wrong? |
Just like sand, but
smaller.
Each tiny piece is
holding its shape. |
Evaluation |
|
Time: 5 |
What the Teacher Will
Do |
Probing Questions |
Student Responses
Potential
Misconceptions |
Have students record
their findings in their journal. |
|
|
Walk through the
classroom offering suggestions, and help if needed. |
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Continue to reinforce
hand signs, and properties. |
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Hold up different
materials worked with in the experiment. |
Can you show me if
this is a solid or a liquid? |
Solid or liquid. |
Continue to help the
children draw the correct conclusion while completing their worksheets. |
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