Grade 8 students use more robust abstract thinking skills to explain causes of complex phenomena and

systems. Many causes are not immediately or physically visible to students. An understanding of cause

and effect of key natural phenomena and designed processes allows students to explain patterns and

make predictions about future events. In grade 8 these include, for example, causes of seasons and

tides; causes of plate tectonics and weather or climate; the role of genetics in reproduction, heredity,

and artificial selection; and how atoms and molecules interact to explain the substances that make up

the world and how materials change. Being able to analyze phenomena for evidence of causes and

processes that often cannot be seen, and being able to conceptualize and describe those, is a significant

outcome for grade 8 students.

ESS1. Earth’s Place in the Universe

8.MS-ESS1-1b. Develop and use a model of the Earth-Sun system to explain the cyclical pattern of

seasons, which includes Earth’s tilt and differential intensity of sunlight on different areas of Earth

across the year.

8.MS-ESS1-2. Explain the role of gravity in ocean tides, the orbital motions of planets, their moons, and

asteroids in the solar system.

8.MS-ESS2-1. Use a model to illustrate that energy from Earth’s interior drives convection that cycles

Earth’s crust, leading to melting, crystallization, weathering, and deformation of large rock formations,

including generation of ocean sea floor at ridges, submergence of ocean sea floor at trenches, mountain

building, and active volcanic chains.

8.MS-ESS2-5. Interpret basic weather data to identify patterns in air mass interactions and the

relationship of those patterns to local weather.

8.MS-ESS2-6. Describe how interactions involving the ocean affect weather and climate on a regional

scale, including the influence of the ocean temperature as mediated by energy input from the Sun and

energy loss due to evaporation or redistribution via ocean currents.

ESS3. Earth and Human Activity

8.MS-ESS3-1. Analyze and interpret data to explain that the Earth’s mineral and fossil fuel resources are

unevenly distributed as a result of geologic processes.

8.MS-ESS3-5. Examine and interpret data to describe the role that human activities have played in

causing the rise in global temperatures over the past century.

LS1. From Molecules to Organisms: Structures and Processes

8.MS-LS1-5. Construct an argument based on evidence for how environmental and genetic factors

influence the growth of organisms.

8.MS-LS1-7. Use informational text to describe that food molecules, including carbohydrates, proteins,

and fats, are broken down and rearranged through chemical reactions forming new molecules that

support cell growth and/or release of energy.

LS3. Heredity: Inheritance and Variation of Traits

8.MS-LS3-1. Develop and use a model to describe that structural changes to genes (mutations) may or

may not result in changes to proteins, and if there are changes to proteins there may be harmful,

beneficial, or neutral changes to traits.

8.MS-LS3-2. Construct an argument based on evidence for how asexual reproduction results in offspring

with identical genetic information and sexual reproduction results in offspring with genetic variation.

Compare and contrast advantages and disadvantages of asexual and sexual reproduction.

8.MS-LS3-3(MA). Communicate through writing and in diagrams that chromosomes contain many

distinct genes and that each gene holds the instructions for the production of specific proteins, which in

turn affects the traits of an individual.

8.MS-LS3-4(MA). Develop and use a model to show that sexually reproducing organisms have two of

each chromosome in their cell nuclei, and hence two variants (alleles) of each gene that can be the same

or different from each other, with one random assortment of each chromosome passed down to

offspring from both parents.

LS4. Biological Evolution: Unity and Diversity

8.MS-LS4-4. Use a model to describe the process of natural selection, in which genetic variations of

some traits in a population increase some individuals’ likelihood of surviving and reproducing in a

changing environment. Provide evidence that natural selection occurs over many generations.

8.MS-LS4-5. Synthesize and communicate information about artificial selection, or the ways in which

humans have changed the inheritance of desired traits in organisms.

8.MS-PS1-1. Develop a model to describe that (a) atoms combine in a multitude of ways to produce

pure substances which make up all of the living and nonliving things that we encounter, (b) atoms form

molecules and compounds that range in size from two to thousands of atoms, and (c) mixtures are

composed of different proportions of pure substances.

8.MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances

interact to determine if a chemical reaction has occurred.

8.MS-PS1-4. Develop a model that describes and predicts changes in particle motion, relative spatial

arrangement, temperature, and state of a pure substance when thermal energy is added or removed.

8.MS-PS1-5. Use a model to explain that atoms are rearranged during a chemical reaction to form new

substances with new properties. Explain that the atoms present in the reactants are all present in the

products and thus the total number of atoms is conserved.

PS2. Motion and Stability: Forces and Interactions

8.MS-PS2-1. Develop a model that demonstrates Newton’s third law involving the motion of two

colliding objects.

8.MS-PS2-2. Provide evidence that the change in an object’s speed depends on the sum of the forces on

the object (the net force) and the mass of the object.