GPHSF logo

Descriptions of Science Fair Categories

The following categories are those recognized by ISEF. Although the Greater Philadelphia Homeschool Science Fair does not separate projects by scientific category, students wishing to compete at the county level (or higher) must designate the category of their science fair projects. Percentages will give you an idea of the relative popularity of each category at one particular county science fair a few years ago. You can see that chemistry was a very popular category (23% of projects were chemistry projects) and therefore much more competitive than microbiology (1% of projects). Keep this in mind when choosing your topic!

Behavior & Social Sciences*

Earth & Space Sciences

Medicine and Health*





Environmental Science





Computer Science


Consumer Science

*These categories (and perhaps others) may require additional paperwork.

Behavior & Social Sciences (8%)

Human and animal behavior, social and community relationships -- psychology, sociology, anthropology, archaeology, ethology, ethnology, linguistics, learning, perception, urban problems, reading problems, public opinion surveys, educational testing, etc.


Biochemistry (2%)

Chemistry of life processes -- molecular biology, molecular genetics, enzymes, photosynthesis, blood chemistry, protein chemistry, food chemistry, hormones, etc.


Botany (11%)

Study of plant life -- agriculture, agronomy, horticulture, forestry, plant taxonomy, plant physiology, plant pathology, plant genetics, hydroponics, etc.


Chemistry (23%)

Study of nature and composition of matter and laws governing it -- physical chemistry, organic chemistry (other than biochemistry), inorganic chemistry, materials, plastics, fuels, pesticides, metallurgy, soil chemistry, etc.


Computer Science (1%)

Study and development of computer hardware, software engineering, internet networking and communications, graphics (including interface), simulations / virtual reality or computational science (including data structures, encryption, coding and information theory), etc. Note: Projects which use existing computers or apply computer procedures to scientific problems should be entered in the area of basic science to which the application is made, not in the Computer Science category.


Earth and Space Sciences (5%)

Geology, mineralogy, physiography, oceanography, meteorology, climatology, astronomy, seismology, geography, topography, speleology, astrophysics, etc.


Engineering (10%)

Technology; projects that directly apply scientific principles to manufacturing and practical uses -- civil, mechanical, aeronautical, chemical, electrical, photographic, sound, automotive, marine, heating and refrigeration, transportation, environmental engineering, power transmission and generation, communications, architecture, bioengineering, lasers, etc.


Environmental Science (8%)

Study of pollution (air, water, and land), sources and their control; ecology.


Gerontology (n/a*)

Study of the aging process in living organisms.

*This is not a separate category in county and regional science fairs. Gerontology projects would thus be entered under another appropriate category at these fairs, such as Medicine & Health or Behavior & Social Sciences.


Mathematics (2%)

Development of formal logical systems or various numerical and algebraic computations and the applicaion of these principles -- calculus, geometry, abstract algebra, number theory, statistics, complex analysis, and probability.


Medicine and Health (5%)

Study of diseases and health of humans and animals -- dentistry, pharmacology, pathology, opthalmology,nutrition, sanitation, pediatrics, dermatology, allergies, speech and hearing, etc.


Microbiology (1%)

Biology of microorganisms -- bacteriology, virology, protozoology, fungi, bacterial genetics, yeast, etc.


Physics (15%)

Theories, principles, and laws governing energy and the effect of energy on matter -- solid state, optics, acoustics, particle, nuclear, atomic, plasma, superconductivity, fluid and gas dynamics, thermodynamics, semiconductors, magnetism, quantum mechanics, biophysics, etc.


Zoology (2%)

Study of animals -- animal genetics, ornithology, ichthyology, herpetology, entomology, animal ecology, paleontology, cellular physiology, circadian rhythms, animal husbandry cytology, histology, animal physiology, invertebrate neurophysiology, studies of invertebrates, etc.


Team Projects (4%)

Study conducted by two or three students in any discipline.


Consumer Science

The science of normal use and comparison of consumer products. (Middle school only.)


Back to Basic Project Timeline

Questions? Contact the GPHSF Director. Last modified: 31 August 2004