Grade Eight

Forums    Curriculum    Professionalism    Events    Links     About     Index    Search

MiddleSchoolScience.org

 

Introduction

The eighth grade units represent topics that are generally more advanced and therefore appropriate to upper middle school learners. All the units build upon fundamental concepts that were learned in previous grades. In order to prepare students for the Intermediate Level Science Exam, teachers need to reinforce concepts learned in earlier grades as appropriate.

CHEMISTRY-

Students will investigate physical and chemical changes and develop mental models to explain common chemical reactions and changes in states of matter.

METEOROLOGY-

Students will learn how the hydrosphere, atmosphere, and lithosphere interact to cause weather and climate.

HEREDITY-

Students will learn that reproduction is characteristic of all living things. Although different organisms have different strategies for reproduction, all organisms pass on hereditary information to the next generation through genes.

MST Standards
Living Environment
Key Idea 2: Organisms inherit genetic information in a variety of ways that result in continuity of structure and function between parents and offspring.
Key Idea 4: The continuity of life is sustained through reproduction and development.
Physical Setting
Key Idea 2: Many of the phenomena that we observe on Earth involve interactions among components of air, water, and land.
Key Idea 3: Matter is made up of particles whose properties determine the observable characteristics of matter and its reactivity.

NYC Science Performance Standards:
The student produces evidence that demonstrates understanding of:
S1a. Properties and changes of properties in matter, such as density and boiling point.
S2b. Reproduction and heredity, such as sexual and asexual reproduction; and the role of genes and environment on trait expression.

Performance Descriptions:
Physical Setting
Eighth grade students will be able to:
2.1: Explain how the atmosphere (air), hydrosphere (water), and lithosphere (land) interact, evolve, and change.
2.2: Explain weather and climate changes.
3.1: Observe and describe properties of materials, such as density, conductivity, and solubility.
3.2: Distinguish between chemical and physical changes.
3.3: Develop mental models to explain chemical reactions and changes in states of matter.
Living Environment
Eighth grade students will be able to:
2.1: Describe sexual and asexual mechanisms for passing genetic materials from generation to generation.
2.2: Describe simple mechanisms related to the inheritance of some physical traits in offspring.
4.1: Observe and describe the variations in reproductive patterns of organisms, including asexual and sexual reproduction.
4.2: Explain the role of sperm and egg in sexual reproduction.
4.4: Observe and describe cell division at the microscopic level and its macroscopic effects.

CORE OBJECTIVES

EXIT PROJECT-

In eighth grade, students will complete one of the following projects: a controlled experiment, a design project, a fieldwork project, or secondary research (see descriptions of each type of project in the Core Objectives for grades 5-7). The completion of this project will fulfill the NYC Grade Eight Exit Project requirement for science. Exit Projects should be integrated into your instructional planning and the other core objectives for grade 8. See Appendix A for more details.

CHEMISTRY-

*Students learned about mixtures and solutions in grade 5. Make sure to review the concepts when discussing solubility as a characteristic property of matter.

  1. Substances have characteristic properties that can be used to help identify different materials. Some of these properties include color, odor, phase at room temperature, density, solubility, heat and electrical conductivity, hardness, and boiling and freezing points. Metric rulers, balances, graduated cylinders, and spring scales can be used to measure many of these properties.
    *Students have already been exposed to the concepts of solids, liquids, and gases in earlier grades. Review the concepts in the context of phase changes below.

  2. During a physical change, no new substances are formed. Examples of physical changes include tearing, crushing, freezing, melting, boiling, evaporation, expansion and contraction.

  3. During a phase change, heat energy is absorbed or released. The motion of particles helps explain phase changes.

  4. Interactions among atoms and molecules result in chemical reactions. During a chemical change, new substances with different properties are created. Examples of chemical changes include burning of wood, cooking of food, rusting of iron, and souring of milk.
    *At this grade level, chemical reactions are better understood through analogy. Students should not be expected to understand the structure of an atom, i.e., electron configurations, isotopes, etc.

  5. All matter is made up of atoms. Atoms may join together in well-defined molecules or regular geometric patterns. Atoms of one element are different from atoms of another element.

  6. There are more than 100 elements that combine in a multitude of ways to produce compounds, which account for all living and nonliving substances that we encounter. Few elements are found in their pure form.

METEOROLOGY-

*Review forces and motion from grade 6 and energy concepts, particularly heat transfer, from grade 7 as appropriate.

  1. The uneven heating of Earth's lithosphere, hydrosphere, and atmosphere causes weather. Cloud cover, temperature, and water vapor concentration affect weather. Weather variables such as wind speed and direction, relative humidity, barometric pressure, and temperature can be measured and recorded on a weather map to help make predictions about the weather.

  2. Climate is the characteristic weather that prevails from season to season and year to year.
    *Review other cycles that students learned about in grade 7.

  3. Water, which covers the majority of the Earth's surface as the hydrosphere, circulates through the crust, oceans, and atmosphere in what is known as the water cycle. Water evaporates from the Earth's surface, rises and cools as it moves to higher elevations, condenses as rain or snow, and falls to the surface, where it collects in lakes, oceans, soil, and in rocks underground.
    *A reminder that students learned about mixtures in grade 5 and reviewed the concepts in the previous chemistry unit. Reinforce the concepts when talking about atmosphere, for example.

  4. The atmosphere is a mixture of nitrogen, oxygen, carbon dioxide, water vapor, and trace gases. The atmosphere has different characteristics at different elevations.
    *This is a good place for students to apply mapping skills learned in social studies class, particularly determining the longitude and latitude of a given location.

  5. Most changes in local weather conditions are caused by movement of air masses. Fronts are boundaries between air masses. The characteristics of an air mass can be predicted based on its origin.
    *Reinforce density and buoyancy concepts in relation to high and low pressure.

  6. High pressure systems usually bring fair weather. Low pressure systems usually bring cloudy, unstable conditions.

  7. Hazardous weather conditions include thunderstorms, tornadoes, hurricanes, ice storms, and blizzards.

HEREDITY-

*In grade 6 students learned about the basic structure of a cell. In this unit they learn a little more detail about the nucleus of a cell including chromosomes. Review basic cell structure and microscope skills.

  1. Hereditary information is contained in genes. Genes are located in the chromosomes of cells.
    *The specifics of DNA transcription, translation, and replication are not appropriate in a middle school classroom.

  2. Each gene carries a single unit of information. A single inherited trait of an individual can be determined by one pair or by many pairs of genes. A human cell contains many thousands of different genes.

  3. In some one-celled organisms, cell division is a method of asexual reproduction. In asexual reproduction, all the genes come from a single parent and all the offspring are genetically identical to the parent.

  4. In sexual reproduction, sperm and egg each carry one-half of the genetic information for the new individual. Therefore, the fertilized egg contains genetic information from each parent.

  5. Sexually produced offspring are not identical to either parent. The probability of traits being expressed in offspring can be determined using models of genetic inheritance. Some models of prediction are pedigree charts and Punnett Squares.

  6. The processes of sexual reproduction and mutation have given rise to a variety of traits within a species.

  7. Genetics describes how traits are passed on from generation to generation in all organisms.

TEACHER RESOURCES

PRENTICE HALL SCIENCE EDITIONS-

NYC RESOURCES-

INTERNET RESOURCES-

Go to the Links page. 

MSSCF Contents

[Introduction] [Matrix] [Guide] [Our Vision]
[Grade 5] [Grade 6] [Grade 7] [Grade 8] [Projects] [Presentations]
[Rubrics & Design Diagrams] [Standards]