5. Prior Knowledge
• Experiences with light, shadows, and darkness
• Prior knowledge may lead them to
o simply not notice a phenomena
o quickly dismiss concepts
o not believe what they do not expect to see.
• Address preconceptions directly
o Reinforce correct facts
o Clarify misconceptions
6. Metacognition
• Young children assume that things are as they appear.
• Science is about questioning
• Explanation is at the heart of scientific activity.
• How can we facilitate Metacognition?
???
7. Teaching Package 1 (30min)
By the end of the lesson, a Primary 4 middle ability
student will be able to recognize that a shadow is
formed when light is completely blocked or partially
blocked by an object.
8. Teaching Package 1
• Watch a video about Hand shadows
Engage •
•
Work on KWL chart
Talk about the phenomena they can explore by showing them materials and equipments to be used in the lesson
KWL chart
What we know What we want What we What I still
to know learned want to know
9. Teaching Package 1
How to cast shadows using cut outs made with different materials.
Explore
•
A B C
D E F
10. Teaching Package 1
Lead students to:
Explain
1. Know the things are needed to cast shadows
2. Describe the shadows that are casted
3. darker shadows are casted by objects that do not allow any light to pass through
4. lighter shadows are casted by objects that allow some light to pass through them
11. Teaching Package 1
• Complete the last two columns of the KWL chart
Closure • Add new facts into concept map for light and shadows
KWL chart
What we know What we want What we What I still
to know learned want to know
12. Teaching Package 2 (60min)
By the end of the lesson, a Primary 4 middle ability
student will learn to:
• investigate shapes and sizes of shadows by
changing the position of the object and the light
source.
• Recognize that an object can cast shadows of
different sizes and shape.
13. Teaching Package 2
• Review the KWL chart
Engage
• Work on anticipation guide
• Talk about the materials and equipments to be used in the lesson
• Watch “Breaking the magician’s code”
Anticipation guide
Agree Disagree
Shadows are alive
The size of the shadow is based upon the
size of the object.
14. Teaching Package 2
• Work in groups to explore how the size of shadows can be changed by varying (1) the distance of the object and (2) light source with respect to the screen/surface.
Explore
• Record the height of the shadow, distance of Lego figure to the screen, distance of light source to the screen.
• Students will key in their data into Google Docs (Assuming that the classroom is equipped with internet connection and 2 computer pushcarts containing 20 laptops each. The student to laptop ratio is 1:1. )
15. Teaching Package 2
• Guide students to analyze the data they have collected.
Explain
Lead students to conclude that:
1. The size of shadows changes as you change the position of the object or the light source
2. When the position of the light source is fixed, the shadow will become bigger if the OBJECT is nearer the light source
3. When the position of the object is fixed, the shadow will become bigger if the Light source is nearer the object
17. Teaching Package 2
Extend • Imagine this, the Lego is standing 30cm away from
the screen. And you move 10cm forward to the
20cm mark. From 1, you would expect your shadow
to be smaller. But by moving the light source
forward to the 70cm mark from 100cm, you can
have the same shadow with the same size !
18.
19.
20. Write in your journal, how the magician is able
to perform the magic trick.
Support your answers using the data which
we have collected.
21. Teaching Package 2
• Review anticipation guide
Closure •
•
Complete the last two columns of the modified KWL chart
Add new facts into concept map for light and shadows
Donovan & Bransford (2005) identifies three principles of learning that teachers of science should utilize in all of their science units. They are: prior knowledge, factual and conceptual knowledge, and Metacognition . Each of these parts will be addressed in helping students to accurately construct knowledge about shadows.
Students need to have both factual and conceptual experiences to develop a full understanding about shadows. Conceptual knowledge helps students to connect individual facts in an organized way; thereby, giving additional meaning to their factual information.
Students have had numerous experiences with light, shadows, and darkness (Magnuson & Palincsar, 2005) which teachers should not ignore. Prior knowledge may lead them to simply not notice, quickly dismiss, or not believe what they do not expect to see. If a teacher of science doesn’t address these preconceptions directly, students resort to memorization of what happens in science class, but still utilize their experience-based preconceptions in their everyday world (Donovan & Bransford, 2005). Teachers need to remember that students’ everyday experiences make sense to them in determining what to trust: everyday experiences or school science
Young children, and indeed many adults, assume that things are as they appear, and no further questioning is required. Science, however, is about questioning—even when something seems obvious—because explanation is at the heart of scientific activity. Teachers can facilitate metacognition by probing students to identify the evidence they are using when reporting their findings (Donovan & Bransford, 2005)
