9th grade Science
28 units matched to the New York State Learning Standards.
Focus areas
- Life science: cells, body systems, DNA, ecosystems and evolution
- Earth science: early Earth, plate tectonics, weather, climate and landscapes
- Space science: the moon, tides, seasons, stars and the universe
- Physical science: atoms, reactions, motion, energy and circuits
Units
Unit 1
Cells from Cells
How cells copy their DNA and divide by mitosis, the stages in order, why cells divide for growth and healing, and what can go wrong when cell growth isn't controlled.
Learning standard: HS-LS1-4 · cell division and growth
Unit 2
Reproduction
How organisms reproduce with one parent or two, why sexual reproduction creates variety, the parts of a flower, and the strengths and weaknesses of each approach.
Learning standard: HS-LS3-2 · how sexual reproduction creates genetic variation
Unit 3
Photosynthesis & Respiration
The reactants, products and location of photosynthesis and cellular respiration, why they are complementary, and how they link plants, animals and the carbon cycle.
Learning standard: HS-LS1-5; HS-LS1-7; HS-LS2-3; HS-LS2-5 · photosynthesis and cellular respiration, and how they cycle carbon and energy through ecosystems and the air
Unit 4
Human Reproductive System
Practices the structure and function of the human reproductive system and the role of hormones, in plain scientific terms. Families may wish to read it together.
Learning standard: HS-LS1-8 · the human reproductive system and how human reproduction and development continue life
Unit 5
Evolution & Selection
Practices variation, adaptation, natural and artificial selection, mutations, the evidence for evolution from fossils and rock layers, and how new species can form.
Learning standard: HS-LS4-1; HS-LS4-2; HS-LS4-4; HS-LS4-5 · natural selection and adaptation, evidence for evolution from fossils and body structures, and how changing environments lead to new species
Unit 6
Atoms & Electrons
Protons, neutrons and electrons, drawing electron shells for the first 20 elements, valence electrons, periodic table groups and periods, and ions and isotopes.
Learning standard: HS-PS1-1 · atomic structure, electron shells and patterns in the periodic table
Unit 7
Electrons & Compounds
How valence electrons decide whether atoms gain, lose or share electrons, ionic and covalent compounds, and reading simple chemical formulas.
Learning standard: HS-PS1-1; HS-PS1-2 · how outer electrons explain bonding and the outcome of simple reactions
Unit 8
Chemical Change
Telling a chemical change from a physical change, reading simple word and symbol equations, why mass is conserved, what speeds a reaction up, exothermic and endothermic changes, and GHS safety.
Learning standard: HS-PS1-2; HS-PS1-5; HS-PS1-7 · chemical reactions, what changes reaction rates, and conservation of atoms and mass
Unit 9
Forces, Motion & Momentum
Practices Newton's second law (F = ma), momentum and its conservation, and designing devices that reduce the force of a collision.
Learning standard: HS-PS2-1; HS-PS2-2; HS-PS2-3 · Newton's second law, conservation of momentum, and designs that reduce collision forces
Unit 10
Energy & Magnetism
Practices the law of conservation of energy, potential and kinetic energy, efficiency, and the link between electric current and magnetic fields in electromagnets and generators.
Learning standard: HS-PS3-1; HS-PS2-5 · conservation of energy and efficiency, and magnetic fields from electric currents
Unit 11
Circuits & Ohm's Law
Circuit components and their jobs, current, potential difference and resistance with their symbols and SI units, calculating with V = I × R, and how current, voltage and resistance behave in series and parallel circuits.
Learning standard: HS-PS3-6 · Ohm's law: how voltage, current and resistance are related in a circuit
Unit 12
Science & Society
Practices weighing the costs and benefits of technologies, spotting unforeseen consequences, taking action on science issues, and linking science to careers and hobbies.
Learning standard: HS-ETS1-3; HS-ESS3-2 · weighing the costs, benefits and trade-offs of technologies and energy solutions
Unit 13
Ecosystem Dynamics
Practices carrying capacity, energy flow and the 10% rule, how ecosystems respond to disturbance, and evaluating solutions to human impacts, using New York's Adirondack lakes, Great Lakes and Hudson River as examples.
Learning standard: HS-LS2-1; HS-LS2-4; HS-LS2-6; HS-LS2-7 · carrying capacity, energy flow, ecosystem stability and reducing human impacts on biodiversity
Unit 14
Body Systems & Homeostasis
Practices the levels of organization in a multicellular organism (cells, tissues, organs and organ systems) and how systems work together, and how feedback loops such as sweating, shivering and insulin keep body temperature, water and blood sugar in a stable range.
Learning standard: HS-LS1-2; HS-LS1-3 · how cells, tissues, organs and systems work together, and how feedback mechanisms maintain homeostasis
Unit 15
DNA, Proteins & Traits
Practices how the order of bases in DNA codes for the order of amino acids in proteins, how cells build carbon-based molecules from sugars and elements like nitrogen, how chromosomes carry genes from parents to offspring, and using Punnett squares and probability to predict how traits are spread in offspring and populations.
Learning standard: HS-LS1-1; HS-LS1-6; HS-LS3-1; HS-LS3-3 · how DNA codes for proteins, how cells build carbon-based molecules, how chromosomes pass on traits, and the probability of inherited traits
Unit 16
Populations & Evolution
Practices using numbers to describe populations and biodiversity, judging the evidence that group behavior such as packs, schools and herds helps animals survive, using proportions to explain how a helpful inherited trait spreads, and how environmental change can grow some populations, form new species and end others.
Learning standard: HS-LS2-2; HS-LS2-8; HS-LS4-3; HS-LS4-5 · population numbers and biodiversity, group behavior and survival, how helpful traits spread, and how environmental change leads to new and extinct species
Unit 17
Plate Tectonics
Practices modeling Earth's interior from seismic evidence, how convection in the mantle moves plates, what happens at each kind of plate boundary, and why ocean crust is young while some continental rock, like the Adirondacks', is over a billion years old.
Learning standard: HS-ESS2-1; HS-ESS2-3; HS-ESS1-5 · Earth's layers and the movement of plates, how plate motion builds and wears down landforms, and the ages of crustal rocks
Unit 18
Earth's Early History
Practices using evidence from meteorites, moon rocks and Earth's oldest minerals to describe how Earth formed about 4.6 billion years ago, and how living things and Earth's systems changed each other, from early microbes adding oxygen to the air to plants building soil.
Learning standard: HS-ESS1-6; HS-ESS2-7 · evidence of Earth's formation and early history, and how Earth's systems and life have changed each other
Unit 19
Air Masses & Fronts
Practices how air masses get their temperature and humidity from where they form, what happens when they meet at cold, warm and stationary fronts, reading front symbols and air pressure, and explaining New York weather such as nor'easters and lake-effect snow.
Learning standard: HS-ESS2-8 · how the movement and meeting of air masses change weather conditions
Unit 20
Engineering for Sustainability
Practices how engineers tackle big challenges such as clean water and pollution: setting criteria and constraints, breaking a problem into smaller parts, using models and computer simulations to test ideas and manage resources sustainably, and refining technologies that reduce human impacts on natural systems.
Learning standard: HS-ESS3-3; HS-ESS3-4; HS-ETS1-1; HS-ETS1-2; HS-ETS1-4 · managing resources sustainably, refining technologies that reduce human impacts, and designing solutions to large challenges with criteria, constraints and simulations
Unit 21
Moon, Tides & Seasons
Practices explaining the repeating cycles of moon phases, eclipses, tides and seasons, and how gravity and Kepler's laws describe the orbits of the moon, planets and satellites.
Learning standard: HS-ESS1-7; HS-ESS1-4 · the cycles of moon phases, eclipses, tides and seasons, and the motion of orbiting objects
Unit 22
Stars & the Universe
Practices how fusion in the sun's core makes the energy that reaches Earth, the life cycles of stars and the elements they make, and the evidence for the Big Bang: galaxies moving apart, leftover microwave radiation and the mix of elements.
Learning standard: HS-ESS1-1; HS-ESS1-2; HS-ESS1-3 · nuclear fusion in the sun, the life cycles of stars and the elements they make, and evidence for the Big Bang
Unit 23
Climate & Earth's Systems
Practices how energy flow and feedbacks among Earth's systems change climate, how carbon cycles through air, oceans, rocks and life, the evidence from ice cores and glaciers, and how people can reduce the causes of climate change.
Learning standard: HS-ESS2-2; HS-ESS2-4; HS-ESS2-6; HS-ESS3-5 · feedbacks among Earth's systems, what changes climate, the carbon cycle, and evidence of climate change
Unit 24
Water, Ice & Landscapes
Practices how water's properties drive weathering, erosion and deposition, how glaciers shaped New York's valleys, lakes and Long Island, and how landforms, water and hazards shape where people live and work.
Learning standard: HS-ESS2-5; HS-ESS3-1 · how water's properties shape Earth's surface, and how resources and natural hazards influence where people live
Unit 25
Waves & Electromagnetic Radiation
Practices the wave equation (speed = frequency × wavelength), the electromagnetic spectrum and why higher-frequency radiation such as ultraviolet and X-rays can harm living tissue, evidence that light acts as both a wave and a particle, why digital transmission is reliable, and devices that use waves, from solar panels to fiber optics.
Learning standard: HS-PS4-1; HS-PS4-2; HS-PS4-3; HS-PS4-4; HS-PS4-5 · the wave equation, digital transmission, the wave and particle models of light, effects of electromagnetic radiation on matter, and devices that use waves
Unit 26
Gases, Solutions, Acids & Bases
Practices how the pressure, volume and temperature of a gas are related, how solutes dissolve and what affects solubility, comparing acids and bases with pH and neutralization, and reactions where electrons move from one substance to another (oxidation and reduction), as in rusting and batteries.
Learning standard: HS-PS1-9; HS-PS1-10; HS-PS1-11; HS-PS1-12 · the combined gas law, the properties of solutions, comparing acids and bases, and reactions that transfer electrons
Unit 27
Nuclear Energy & Bond Energy
Practices how nuclei change in fission, fusion and radioactive decay, what alpha, beta and gamma radiation are, half-life calculations, and how the energy absorbed to break bonds and released to form bonds makes a reaction give off or take in energy.
Learning standard: HS-PS1-8; HS-PS1-4 · changes in the nucleus during fission, fusion and radioactive decay, and how breaking and forming bonds releases or absorbs energy
Unit 28
Forces at a Distance & Heat Flow
Practices reasoning with Newton's law of gravitation and Coulomb's law (how forces change when masses, charges or distances change), and how thermal energy flows from hotter to colder objects until they reach the same temperature, including simple mixing calculations.
Learning standard: HS-PS2-4; HS-PS3-4 · how gravitational and electric forces depend on mass, charge and distance, and how thermal energy flows until objects reach the same temperature
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