Education.com

National Standards for Grade 8 - Science (page 5)

National Assessment Governing Board

Models

The models theme has been selected because of the importance of enabling students to distinguish the idealizations of models from the phenomena themselves. Students need to understand that a model of the human eye does not represent all aspects of human eyes as they occur in human organisms. The model is a simplification, leaving unrepresented many important variations in human eye structure, yet the simplification has utility in illuminating some features of the eye and enables new questions about the eye to be generated.

Students need to understand the limitations and simplifying assumptions that underlie the varied models used in the natural sciences. For example, beliefs that models are replicas of real objects or events can negate the critical concept of variation that many models do not take into account. Although generalized models, such as a generalized graph of growth in populations, are useful, they are not to be confused with a graph of the growth of a particular organism or population or with a graph of data from a single experiment.

Grade 8

Students should have knowledge of both conceptual and physical models and their uses and limitations. For example, when asked to illustrate their understanding of vertebrate structure and function with models of skeletons of different vertebrates, students need to be aware of variations in real skeletons and the generalized nature of the replicas.

Example Science Content Standards

Grade - Life Science

A. Cells and their functions

1. Cells:

Students can describe their observations of cells under the microscope:

  • Students can demonstrate the use of a microscope to examine a tissue, plant, or animal and to differentiate between plant and animal cells (for example, students can look at an animal cell and a plant cell and notice that an animal cell is flexible and a plant cell is not) (Scientific Investigation, Systems);
  • Students can look at pond water through a microscope and describe outstanding features/activities of the protista they see (for example, locomotion, nutrition, excretion) (Scientific Investigation).
  • Students can observe diatoms and try to distinguish as many features as possible (Scientific Investigation).
  • Students can explain, in a general way, the advantages of cellular interdependence versus independence (for example, multicellular animals versus single-celled animals).
  • Students can describe, in general terms, the difference between asexual and sexual reproduction in cells and the advantages and disadvantages of each (the stages of mitosis are not to be tested).

B. Organisms

1. Reproduction, growth, and development:

Students can describe growth, development, and reproduction of the human organism:

  • Students can identify the age ranges at which human beings go through common stages of development (for example, can recognize their parents; can learn to walk, talk, and socialize; can conceive or give birth) (Conceptual Understanding, Patterns of Change).
  • Students can identify the changes human beings undergo at puberty and can explain their functions (Conceptual Understanding, Patterns of Change).
  • Students can, in simple terms, describe changes in human embryo development and the effects of environmental influences such as smoking, drugs, disease, and the mother’s diet on the development of the embryo (Conceptual Understanding, Patterns of Change).

2. Life cycles:

Students can identify some major influences on the human life cycle (for example, diet, disease):

  • Students can discuss the influence of diet and food availability on human life cycles worldwide (Practical Reasoning, Patterns of Change).
  • Students can explain that microorganisms can cause disease and can identify some common diseases caused by microorganisms such as bacteria, viruses, protista (differences between viruses and bacteria are not to be tested) (Conceptual Understanding).
  • Students can describe the immune system of animals as helping the animal fight disease and as controlled, in part, by the white blood cells in the body (Conceptual Understanding).

3. Functions and interactions of systems within organisms:

  • Students are aware that, although different systems of the body have different functions, the functioning of each system affects other systems (for example, students can describe/identify major organ systems of the human body, state their major functions, and describe some of their interactions):

  • Students can describe the primary tissues of the body (for example, blood, lymph, muscle) and relate the special characteristics of each to its function (Conceptual Understanding, Systems).
  • Students can distinguish cells from other structures under the microscope (for example, between an onion cell and a salt crystal) (Scientific Investigation, Systems).

Students can describe how two or more organs of the body work together to perform a function (for example, the heart and lungs working together in respiration) (Conceptual Understanding, Systems).

Students demonstrate an understanding of the functions and interactions of organ systems to maintain a stable internal environment that can resist disturbances from within or without (homeostasis). 

View Full Article

Add your own comment

Ask a Question

Have questions about this article or topic? Ask
Ask
150 Characters allowed

Today on Education.com

WE'VE GOT A GREAT ROUND-UP OF ACTIVITIES PERFECT FOR LONG WEEKENDS, STAYCATIONS, VACATIONS ... OR JUST SOME GOOD OLD-FASHIONED FUN!

We've got a great round-up of activities perfect for long weekends, staycations, vacations ... or just some good old-fashioned fun! Get Outside! 10 Playful Activities

Washington Virtual Academies

Tuition-free online school for Washington students.