Grade Eight Item Specifications - CAASPPStudent correctly determined whether a chemical reaction occurred based on observations and/or empirical data of physical and chemical properties

Grade Eight Item Specifications |

2017–18 CAST Academy

DRAFT–This document will be revised in fall 2018.

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Grade Eight Item Specifications

Note: Refer to the MS-PS1-2 Matter and its Interactions Web page for the full information for this screenshot.

Dimensions Standards

Sub-Practice 4.2 Ability to analyze data to identify relationships

Sub-Practice Assessment Targets

4.2.1 Ability to use observational and/or empirical data to describe patterns and relationships

DCI Assessment Targets

Student can:

PS1.A.8a Identify characteristic physical properties of pure substances (e.g. color, smell, boiling point, melting point, and density).

https://www.nextgenscience.org/pe/ms-ps1-2-matter-and-its-interactions




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PS1.A.8b Identify characteristic chemical properties of pure substances (e.g. flammability).

PS1.B.4a Describe that during a chemical reaction the atoms that make up the original substances (reactants) are rearranged to form new substances (products).

PS1.B.4b Describe that the properties of the reactants are different than the properties of the products.

PS1.B.4c Determine whether a chemical reaction has occurred based on the properties of the reactants and the products.


Student can:

CCC1 Identify macroscopic patterns that are related to the nature of microscopic and atomic-level structure.

Possible Phenomena or Contexts*

Possible contexts include:

Combustion reactions

Replacement (displacement) reactions that produce a gas, precipitate, or color change

Synthesis and decomposition reactions

Examples of Integration of Assessment Targets and Evidence*

Task provides data on physical and chemical properties of a pure substance:

Student correctly determines which element is represented. (4.2.1-1a & PS1.A.8)

Task provides a pure substance:

Student correctly identifies characteristic chemical properties of the substance. (4.2.1-1b, PS1.A.8 & CCC1)

Task provides a scenario involving a chemical reaction or set of reactions:

Student correctly interprets the observations and data and describes how the observations and data indicate that a chemical change has occurred. (4.2.1-1c, PS1.B.4 & CCC1)




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Student describes how the properties of the reactants and products are different. (4.2.1-1d, PS1.B.4 & CCC1)

Task provides a set of reactants and a set of products:

Student correctly determined whether a chemical reaction occurred based on observations and/or empirical data of physical and chemical properties. (4.2.1-1e, PS1.B.4 & CCC1)

Common Misconceptions*

All physical changes are reversible/all chemical changes are irreversible.

Changes of state are chemical changes.

Chemical changes always occur when substances are mixed/dissolved.

An increase or decrease in the temperature of a chemical system always indicates a chemical change.

Additional Assessment Boundaries

N/A

*Not an exhaustive list

Additional References (if any)

National Research Council. (2010). Committee for the Workshops on Computational Thinking: Report of a workshop on the scope and nature of computational thinking. Washington, DC: National Academies Press.

Nakhleh, M. B. (1992). Why some students don't learn chemistry: Chemical misconceptions. J. Chem. Educ, 69(3), 191.

Kind, V. (2004). Beyond appearances: Students’ misconceptions about basic chemical ideas. School of Education, Durham University, UK.




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Evidence Statements for MS-PS1-2

Observable features of the student performance by the end of the course:

1. Organizing data

a. Students organize given data about the characteristic physical and chemical properties (e.g., density, melting point, boiling point, solubility, flammability, odor) of pure substances before and after they interact.

b. Students organize the given data in a way that facilitates analysis and interpretation.

2. Identifying relationships

a. Students analyze the data to identify patterns (i.e., similarities and differences), including the changes in physical and chemical properties of each substance before and after the interaction (e.g., before the interaction, a substance burns, while after the interaction, the resulting substance does not burn).

3. Interpreting data

a. Students use the analyzed data to determine whether a chemical reaction has occurred.

b. Students support their interpretation of the data by describing that the change in properties of substances is related to the rearrangement of atoms in the reactants and products in a chemical reaction (e.g., when a reaction has occurred, atoms from the substances present before the interaction must have been rearranged into new configurations, resulting in the properties of new substances).




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Note: Refer to the MS-PS1-5 Matter and its Interactions Web page for the full information for this screenshot.


Sub-Practice 2.1 Ability to develop a model

2.2 Ability to use models


2.1.1 Ability to determine the components as well as relationships among multiple components, to include or omit, of a scientific event, system, or design solution

2.2.2 Ability to use the model to generate explanations and predictions about the behavior of a scientific phenomenon

https://www.nextgenscience.org/pe/ms-ps1-5-matter-and-its-interactions




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Student can:

PS1.B.5a Describe that during a chemical reaction the atoms that make up the reactants are rearranged to form new products.

PS1.B.5b Identify and describe the number and types of atoms in a molecule of a substance based on a chemical formula and/or molecular model.

PS1.B.5c Describe that each type of atom has a specific mass, which is the same for all atoms of that type.

PS1.B.5d Describe that the number and types of atoms in the reactants are equal to the number and types of atoms in the products.

PS1.B.5e Describe that atoms and thus mass are conserved during chemical reactions.

PS1.B.5f Recognize the components, relationships, and predictive power of a balanced chemical equation.

CCC Assessment Targets

Student can:

CCC5 Identify that matter is conserved because atoms are conserved in physical and chemical processes.



Simple, one-directional reactions representing combustion, synthesis, decomposition, and replacement

Reaction involving a limiting reagent


Task provides description of a chemical reaction and a list of relevant and irrelevant components:

Student correctly selects the appropriate components to develop the model to illustrate the conservation of atoms/mass. (2.1.1-1a & PS1.B.5, & CCC5)

Task provides an incomplete model of a chemical reaction and a list of relevant and irrelevant components:




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Student correctly selects the appropriate components to complete the model to illustrate the conservation of atoms/mass. (2.1.1-2a, PS1.B.5, & CCC5)

Task provides a model of a chemical reaction that illustrates the conservation of atoms/mass:

Student correctly identifies the explanation that the model is trying to convey. (2.2.2-1a & PS1.B.5, & CCC5)

Student correctly identifies the predictive meaning of the model. (2.2.2-1b & PS1.B.5, & CCC5)

Student uses the model to make a correct prediction. (2.2.2-1c & PS1.B.5, & CCC5)


Atoms and molecules are the same thing.

The number of molecules before and after a reaction should be equal.

Mass is lost or gained in certain reactions out of nowhere.

Mass of an atom changes during a chemical reaction.

Chemical reactions cause changes to atoms, not molecules.


N/A



Barker, V. (2002). Beyond misconceptions: Students’ misconceptions about basic chemical ideas. London: Royal Society of Chemistry.




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1. Components of the model

a. To make sense of a given phenomenon, students develop a model in which they identify the relevant components for a given chemical reaction, including:

i. The types and number of molecules that make up the reactants. ii. The types and number of molecules that make up the products.

2. Relationships

a. In the model, students describe relationships between the components, including:

i. Each molecule in each of the reactants is made up of the same type(s) and number of atoms.

ii. When a chemical reaction occurs, the atoms that make up the molecules of reactants rearrange and form new molecules (i.e., products).

iii. The number and types of atoms that make up the products are equal to the number and types of atoms that make up the reactants.

iv. Each type of atom has a specific mass, which is the same for all atoms of that type.

3. Connections

a. Students use the model to describe that the atoms that make up the reactants rearrange and come together in different arrangements to form the products of a reaction.

b. Students use the model to provide a causal account that mass is conserved during chemical reactions because the number and types of atoms that are in the reactants equal the number and types of atoms that are in the products, and all atoms of the same type have the same mass regardless of the molecule in which they are found.




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Note: Refer to the MS-PS3-1 Energy Web page for the full information for this screenshot.


Sub-Practice 4.1 Ability to record and organize data

4.2 Ability to analyze data to identify relationships


4.1.3 Ability to organize data in a way that facilitates analysis and interpretation


4.2.2 Ability to identify patterns (qualitative or quantitative) among variables represented in data


Student can:

PS3.A.6a Demonstrate through graphical displays that when the mass and/or the speed of an object increases, the kinetic energy increases.

https://www.nextgenscience.org/pe/ms-ps3-1-energy




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PS3.A.6b Demonstrate through graphical displays that when the mass and/or the speed of an object decreases, the kinetic energy decreases.

PS3.A.6c Demonstrate through graphical displays that kinetic energy and mass have a linear proportional relationship.

PS3.A.6d Demonstrate through graphical displays that kinetic energy and speed have a proportional relationship that is nonlinear.

PS3.A.6e Draw comparisons between the rate of change between mass and kinetic energy, and speed and kinetic energy (i.e., the kinetic energy doubles as the mass of the object doubles, yet the kinetic energy quadruples as the speed of the object doubles).


Student can:

CCC3 Identify proportional relationships (e.g. speed as the ratio of distance traveled to time taken) among different types of quantities that provide information about the magnitude of properties and processes.



Damage done by objects of different masses moving at the same speed or objects of the same mass moving at different speeds

Distance traveled after objects of different masses roll down a ramp, released from a catapult, or some other source of kinetic energy




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Task provides data showing indentations made when objects of different masses hit a barrier:

Student correctly states that the different masses make different indentations along barrier upon impact. (4.1.3-1a, PS3.A.6 & CCC3)

Student correctly graphs the relationship between mass/speed and the depth of the indentation. (4.1.3-1b, PS3.A.6 & CCC3)

Student uses their generated graph to correctly identify a pattern between the masses or velocities of the object and the indentation along the barrier. (4.1.3-1c, PS3.A.6 & CCC3)

Task provides a graph of an increase in mass versus kinetic energy and/or a graph of an increase in velocity versus kinetic energy:

Students correctly describe the relationship shown by the graph as linear or non-linear. (4.2.1-1a, PS3.A.6 & CCC3)

Task provides an interactive model where the mass and velocity of an object in motion can be varied and the object’s kinetic energy is displayed:

Student correctly states that increasing the object’s mass results in a directly proportional increase of the object’s kinetic energy. (4.2.2-1a, PS3.A.6 & CCC3)

Student correctly states that increasing the object’s speed results in an increase of the object’s kinetic energy proportional to the square of its speed. (4.2.2-1b, PS3.A.6 & CCC3)


A lighter object has more kinetic energy than a heavy one.

The motion of an object depends on its size.

The material make-up of an object affects its kinetic energy.

Inanimate objects do not have energy associated with them.




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Kinetic energy depends on its direction of travel.

Kinetic Energy only depends on mass or speed

Kinetic Energy equally depends on mass and speed


N/A



AAAS Science Assessment Beta. (2017). AAAS science assessment ~ topics ~ energy: forms, tranformations, transfer, and conservation. American Association for the Advancement of Science. Retrieved from: http://assessment.aaas.org/topics/EG#/,tabs-215/2

Neumann, K., Viering, T., Boone, W. J., & Fischer, H. E. (2012). Towards a learning progression of energy. Journal of Research in Science Teaching, 50(2), 162-188. doi:10.1002/tea.21061

http://assessment.aaas.org/topics/EG%23/,tabs-215/2

http://assessment.aaas.org/topics/EG%23/,tabs-215/2




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1. Organizing data

a. Students use graphical displays to organize the following given data:

i. Mass of the object. ii. Speed of the object. iii. Kinetic energy of the object.

b. Students organize the data in a way that facilitates analysis and interpretation.


a. Using the graphical display, students identify that kinetic energy:

i. Increases if either the mass or the speed of the object increases or if both increase.

ii. Decreases if either the mass or the speed of the object decreases or if both decrease.


a. Using the analyzed data, students describe:

i. The relationship between kinetic energy and mass as a linear proportional relationship (KE m) in which:

1. The kinetic energy doubles as the mass of the object doubles. 2. The kinetic energy halves as the mass of the object halves.

ii. The relationship between kinetic energy and speed as a nonlinear (square) proportional relationship (KE v2) in which:

1. The kinetic energy quadruples as the speed of the object doubles.

2. The kinetic energy decreases by a factor of four as the speed of the object is cut in half.




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Note: Refer to the MS-LS2-1 Ecosystems: Interactions, Energy, and Dynamics Web page for the full information for this screenshot.


Sub-Practice 4.2 Ability to analyze data to identify relationships



4.2.2 Ability to identify patterns (qualitative or quantitative) among variables represented in data

https://www.nextgenscience.org/pe/ms-ls2-1-ecosystems-interactions-energy-and-dynamics




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Student can:

LS2.A.4a Describe that individual organisms depend on biotic and abiotic factors and the interactions between these factors for survival.

LS2.A.4b Describe that populations of organisms are affected by biotic and abiotic factors and the interactions between these factors.

LS2.A.5a Describe that competition between individuals of a single species (intraspecific competition) for available resources occurs.

LS2.A.5b Describe that competition between individuals from different species (interspecific competition) for available resources occurs.

LS2.A.6a Describe that growth of an organism is limited by availability of resources.

LS2.A.6b Describe that population growth is limited by availability of resources.


Student can:

CCC2 Use cause and effect relationships to predict phenomena in natural or designed systems.



Habitats with highly limited resources

Seasonal changes to resource availability

Introduction of a new species to existing community

An environmental change that alters resource availability

Increased competition


Task provides a data set showing the numbers of individuals in a population during different months of the year:

Student correctly identifies patterns of change. (4.2.1-1a, LS2.A.4, & CCC2)




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Task provides a simulation that provides data showing populations of various organisms following a large environmental change (e.g., a forest fire, flooding, etc.):

Student correctly predicts the likely outcome for the organisms following the environmental change. (4.2.2-1a, LS2.A.4, & CCC2)

Task provides data comparing population growth when resources are nonlimiting and limiting:

Student correctly describes the differences in the models. (4.2.2-1b, LS2.A.6, & CCC2)

Student correctly explains why the models are different. (4.2.2-1c, LS2.A.6 &, CCC2)

Task provides data for a community before and after the introduction of an invasive species:

Student correctly describes the changes in interspecies competition introduced by the invasive species. (4.2.2-1d, LS2.A.5, & CCC2)


Animals do not compete with others of their species for a limited set of resources (e.g., all the squirrels are friends).

Since natural resources, like wood and water, are renewable, they cannot be used up and do not limit population growth.

Plants do not exhibit competition for resources.

Changes in populations or resource availability only affect resources/organisms that are directly connected in a food chain.


N/A





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Manz, E. (2012). Understanding the codevelopment of modeling practice and ecological knowledge. Science Education, 96(6), 1071-1105. doi:10.1002/sce.21030

Munson, B. H. (1994). Ecological Misconceptions. The Journal of Environmental Education, 25(4), 30-34. doi:10.1080/00958964.1994.9941962

Songer, N. B., Kelcey, B., & Gotwals, A. W. (2009). How and when does complex reasoning occur? Empirically driven development of a learning progression focused on complex reasoning about biodiversity. Journal of Research in Science Teaching, 46(6), 610-631. doi:10.1002/tea.20313




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Evidence Statements for MS-LS2-1


1. Organizing data

a. Students organize the given data (e.g., using tables, graphs, and charts) to allow for analysis and interpretation of relationships between resource availability and organisms in an ecosystem, including:

i. Populations (e.g., sizes, reproduction rates, growth information) of organisms as a function of resource availability.

ii. Growth of individual organisms as a function of resource availability.


a. Students analyze the organized data to determine the relationships between the size of a population, the growth and survival of individual organisms, and resource availability.

b. Students determine whether the relationships provide evidence of a causal link between these factors.


a. Students analyze and interpret the organized data to make predictions based on evidence of causal relationships between resource availability, organisms, and organism populations. Students make relevant predictions, including:

i. Changes in the amount and availability of a given resource (e.g., less food) may result in changes in the population of an organism (e.g., less food results in fewer organisms).

ii. Changes in the amount or availability of a resource (e.g., more food) may result in changes in the growth of individual organisms (e.g., more food results in faster growth).

iii. Resource availability drives competition among organisms, both within a population as well as between populations.

iv. Resource availability may have effects on a population’s rate of reproduction.




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Note: Refer to the MS-ESS1-1 Earth’s Place in the Universe Web page for the full information for this screenshot.


Sub-Practice 2.1 Ability to develop models

2.2 Ability to use models

2.3 Ability to evaluate and revise models


2.1.1 Ability to determine the components as well as relationships among multiple components, to include or omit, of a scientific event, system, or design solution

2.2.1 Ability to use the model to collect evidence to reason qualitatively or quantitatively about concepts and relationships represented in the model

https://www.nextgenscience.org/pe/ms-ess1-1-earths-place-universe




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2.2.2 Ability to use the model to generate explanations and predictions about the behavior of a scientific phenomenon

2.3.2 Ability to revise models in light of empirical evidence to improve their explanatory and predictive power


Student can:

ESS1.A.3a Model the arcing paths of the Sun, Moon, and stars through the night’s sky in relation to Earth’s axis.

ESS1.B.4a Describe the spatial and temporal relationships among the Earth-Moon-Sun system.

ESS1.B.4b Identify the Sun as the original source of light/energy that illuminates the Moon and warms Earth.

ESS1.B.4c Model the path of light from a source as a line directed towards another object and the behaviors of light (e.g., reflection).

ESS1.B.4d Explain lunar phases in terms of the relative positions of the Sun, Earth, and Moon.

ESS1.B.4e Describe how the Moon’s equal rotational and orbital speeds results in the inability to see the far side of the Moon from Earth.

ESS1.B.4f Ability to identify and describe the role of the tilt in the Moon’s orbital plane with respect to Earth’s orbit around the Sun in terms of the frequency and type of lunar and solar eclipses.

ESS1.B.4g Identify and describe the role of Earth’s axial tilt in causing seasons despite minimal change in the proximity to the Sun.

ESS1.B.4h Contrast sunlight received by the Northern and Southern Hemispheres leading to opposite experiences of winter/summer.


Student can:

CCC1 Use patterns to identify cause-and-effect relationships.




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Phenomena associated with timing and appearance of eclipses

The differences in seasons in the northern vs. southern hemisphere

The seasonal changes observed in the patterns of movement of the Moon, Sun, and other objects in the sky


Task provides a phenomenon related to the Earth-Moon-Sun system and a list of relevant and irrelevant components, labels, or other representations for a model:

Student correctly identifies appropriate components needed to develop a model to explain the phenomenon. (2.1.1-1a & ESS1.B.4)

Task provides an incomplete or incorrect model of a phenomenon related to the Earth-Moon-Sun system and a list of relevant and irrelevant components, labels, or other representations:

Student correctly identifies the components, labels, or representation to complete the model to explain the phenomena. (2.1.1-2a & ESS1.B.4)

Task provides evidence generated from a model representing a phenomenon related to the Earth-Moon-Sun system and a driving question or hypothesis:

Student uses evidence generated from the model to answer the question or support/refute the hypothesis. (2.2.1-2a & ESS1.B.4)

Task provides a model representing a phenomenon related to the Earth-Moon-Sun model:

Student correctly identifies the relationships between components of the model based on the evidence. (2.2.1-2b & ESS1.B.4)

Task provides a model and a phenomenon related to the Earth-Moon-Sun system:




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Student correctly identifies the explanation that the model is trying to convey. (2.2.2-1a & ESS1.B.4)

Student correctly identifies the predictive meaning of the model. (2.2.2-1b, ESS1.B.4 & CCC1)

Student correctly uses the model to make a prediction. (2.2.2-1c, ESS1.B.4 & CCC1)

Student manipulates the model to correctly depict an explanation of the observed phenomenon. (2.2.2-1d & ESS1.B.4)

Task provides a model with a limitation in representing a phenomenon related to the Earth-Moon-Sun system:

Student correctly identifies a revision that improves the model’s explanatory or predictive power. (2.3.2-1a & ESS1.B.4)

Student correctly identifies the rationale for revising the model. (2.3.2-2a & ESS1.B.4)


The dark side of the Moon does not receive light from the Sun.

All objects within the solar system orbit on the same plane.

The distance between Earth and the Sun is the primary cause of seasons.


N/A



National Research Council. (2012). A framework for K-12 science education: Practices, crosscutting concepts, and core ideas. Washington, D.C.: National Academies Press.

NGSS Lead States. 2013. Next Generation Science Standards: For States, By States (Appendix E). Washington, DC: The National Academies Press.




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Plummer, J. D., & Krajcik, J. (2010). Building a learning progression for celestial motion: Elementary levels from an earth-based perspective. Journal of Research in Science Teaching, 47, 768-787. doi:10.1002/tea.20355

Rivet, A. E., & Kastens, K. A. (2012). Developing a construct-based assessment to examine students' analogical reasoning around physical models in Earth Science. Journal of Research in Science Teaching, 49, 713-743. doi:10.1002/tea.21029




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Evidence Statements for MS-ESS1-1


1. Components of the model

a. To make sense of a given phenomenon, students develop a model (e.g., physical, conceptual, graphical) of the Earth-moon-sun system in which they identify the relevant components, including:

i. Earth, including the tilt of its axis of rotation. ii. Sun. iii. Moon. iv. Solar energy.

b. Students indicate the accuracy of size and distance (scale) relationships within the model, including any scale limitations within the model.

2. Relationships

a. In their model, students describe the relationships between components, including:

i. Earth rotates on its tilted axis once an Earth day. ii. The moon rotates on its axis approximately once a month. iii. Relationships between Earth and the moon:

1. The moon orbits Earth approximately once a month.

2. The moon rotates on its axis at the same rate at which it orbits Earth so that the side of the moon that faces Earth remains the same as it orbits.

3. The moon’s orbital plane is tilted with respect to the plane of the Earth’s orbit around the sun.

iv. Relationships between the Earth-moon system and the sun:

1. Earth-moon system orbits the sun once an Earth year.

2. Solar energy travels in a straight line from the sun to Earth and the moon so that the side of the Earth or the moon that faces the sun is illuminated.

3. Solar energy reflects off of the side of the moon that faces the sun and can travel to Earth.

4. The distance between Earth and the sun stays relatively constant throughout the Earth’s orbit.




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5. Solar energy travels in a straight line from the sun and hits different parts of the curved Earth at different angles—more directly at the equator and less directly at the poles.

6. The Earth’s rotation axis is tilted with respect to its orbital plane around the sun. Earth maintains the same relative orientation in space, with its North Pole pointed toward the North Stare throughout its orbit.

3. Connections

a. Students use patterns observed from their model to provide causal accounts for events, including:

i. Moon phases:

1. Solar energy coming from the sun bounces off of the moon and is viewed on Earth as the bright part of the moon.

2. The visible proportion of the illuminated part of the moon (as viewed from Earth) changes over the course of a month as the location of the moon relative to Earth and the sun changes.

3. The moon appears to become more fully illuminated until “full” and then less fully illuminated until dark, or “new,” in a pattern of change that corresponds to what proportion of the illuminated part of the moon is visible from Earth.

ii. Eclipses:

1. Solar energy is prevented from reaching the Earth during a solar eclipse because the moon is located between the sun and Earth.

2. Solar energy is prevented from reaching the moon (and thus reflecting off of the moon to the Earth) during a lunar eclipse because Earth is located between the sun and moon.

3. Because the moon’s orbital plane is tilted with respect to the plane of the Earth’s orbit around the sun, for a majority of time during an Earth month, the moon is not in a position to block solar energy from reaching Earth, and Earth is not in a position to block solar energy from reaching the moon.

iii. Seasons:

1. Because the Earth’s axis is tilted, the most direct and intense solar energy occurs over the summer months, and the least direct and intense solar energy occurs over the winter months.




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2. The change in season at a given place on Earth is directly related to the orientation of the tilted Earth and the position of Earth in its orbit around the sun because of the change in the directness and intensity of the solar energy at that place over the course of the year.

a. Summer occurs in the Northern Hemisphere at times in the Earth’s orbit when the northern axis of Earth is tilted toward the sun. Summer occurs in the Southern Hemisphere at times in the Earth’s orbit when the southern axis of Earth is tilted toward the sun.

b. Winter occurs in the Northern Hemisphere at times in the Earth’s orbit when the northern axis of Earth is tilted away from the sun. Summer occurs in the Southern Hemisphere at times in the earth’s orbit when the southern axis of Earth is tilted away from the sun.

b. Students use their model to predict:

i. The phase of the moon when given the relative locations of the Earth, sun, and moon.

ii. The relative positions of the Earth, sun, and moon when given a moon phase.

iii. Whether an eclipse will occur, given the relative locations of the Earth, sun, and moon and a position on Earth from which the moon or sun can be viewed (depending on the type of eclipse).

iv. The relative positions of the Earth, sun, and moon, given a type of eclipse and a position on Earth from which the moon/sun can be viewed.

Documents

Grade Eight Item Specifications - CAASPPStudent correctly determined whether a chemical reaction occurred based on observations and/or empirical data of physical and chemical properties