NSDL Science Refreshers provide quick and easy access to high-quality science content. These resources from trusted providers are selected and organized by grade level and subject area in order to save you time and effort in finding interactive tutorials, diagrams, articles, and other materials to enhance your content knowledge.
Though titled for kids the information presented at this site is thorough and supported with hot links to related concepts as well as illustrations. Click on the blue Next Stop on the Tour button to continue learning.
Most non-permanent markers use inks that are made of mixtures of colored pigments and water. How does Black Magic work? Why do some black inks separate into many colors on a wet coffee filter? Why does mixing many colors of ink make black?
This short article describes the common properties of all carbon containing compounds and points out that basis of life's molecules is carbon, thus carbon compounds are ubiquitous in living things.
These pages are set up like a self guided tutorial. Click on the next stop on the tour button at the bottom of each page to learn more about matter, states of matter and the particulate nature of matter.
This is an online interactive periodic table of the elements which includes all elements up to 118. There are several different options for viewing, such as date of discovery, electron configuration, number of neutrons, etc. Elements can also be viewed by element groups. Additional links to further information on a particular element are given in some cases. Citation information is also provided.
Though titled for kids the information presented at this site is thorough and supported with hot links to related concepts as well as illustrations. Click on the blue Next Stop on the Tour button to continue learning.
This article describes what comets are in general, some specific comets, and some astronomers associated with finding and understanding comets. Photographs are included.
This page from a comprehensive physics site, describes, defines, and illustrates electrical conductivity. Click on Resistance in the right hand navigation bar for similar information regarding conductivity's opposite, resistivity.
Taxa of Eubacteria, with links to more information on bacteria.
The user can vary the strength of the selection pressure, a predator, pathogen, or pollution for example, which is how change in the environment is simulated. Mutation rates can also be varied. The interaction of these two variables gives rise to adaptations, thus evolution. However, the same two variables also explain extinctions when random mutations produce traits which decrease, rather than increase fitness and/or when environmental change is so severe, a large proportion of a species is killed off in a few generations, not leaving enough individuals to repopulate before other species' outcompete the now rare species.
Article describes natural selection, its dependence on genetic variation and the role of the changing environment in natural selection.
This is an activity featuring a time zone map useful when teaching an interdisciplinary social studies and math unit focusing on geography and the time zones. It underscores the role of the earth's rotation in everyday life, and the need to understand the relationships between earth rotation, day and night, and time zones around the world.
This article tells how the freezing point of a substance is also its melting point. The energy of the substance's molecules changes with temperature, thus with changes in state. Also described is how freezing points can be lowered, or depressed, by adding a substance.
Shows a phylogenetic tree of the fungi phyla, followed by information, photos and more links. Click on the hotlinks in the phylogenetic tree for specific examples within the phyla also accompanied by photos.
Color photomicrographs of several species of green algae with brief descriptions of their chief characteristics and habitat. Scroll to the bottom of the page to links to bacteria, and more protists including diatoms, desmids and rotifers.
This page is all about the formation of the universe and its structure. Several hotlinks are embedded in the discussion for further information. Photographs from the Hubble Space telescope are included.
A one page article describing the formation of fossil fuels, enhanced with illustrations. At its end, there are three links to specific fuels: coal, oil and gas for more specific information.
This web site answers the following questions: What happens in reflection? What causes absorption? and How is the transmitted amount calculated?
This article is divided into pages on bulb thermometers, bimetallic, strip thermometers, and electronic thermometers. Illustrations are included.
Article describing Lamarckism, the erroneous idea that acquired characteristics are heritable, and its history with hot links to natural selection, adaptation, and more.