The first place to look is the inside cover of any physics textbook, particularly the freshman level introductory books. There is a list of constants there. (Below is a link to a "wall chart" of dozens of constants. Have you ever thought about how people know these values?
Pick one that you are curious about and start googling its name. Modify your search to include terms like "history of" or "meaning of". Don't spend much time on this -- it's just to give you a sense of whether your curiosity about the constant will carry you through the semester. This is a good time to browse Wikipedia.
The National Institute of Standards and Technology also maintains a page devoted to the constants. It gives values, descriptions of history and meaning, and other background information. The link is below.
Finally, you should exploit the library. Search through the NC-PALS database for a book we have that relates to your constant. Go to the shelves and find that book. Look at the books around it on the shelf in the same area. See if you can find a few that give you basic information about your constant.
Another good place to start is Google Books. Although I still think there is something to be gained from actually physically going into the stacks, this can't hurt.
There will be two phases to your background research: you will need to study the meaning and importance of the constant you have chosen, and then you will have to research the ways that constant can be measured, to determine whether any of them are feasible for our class resources.
For the first phase, you will probably want to consult books. There are some web sites that can get you started, but you'll want to move past them fairly quickly. Remember, Wikipedia is a great place to start looking, and a terrible place to stop looking. Anything you think you might want to cite from a Wikipedia page, make sure you find it in a book or article, as well, and cite the published source instead.
Students have a watershed moment when they discover that books:
-Can provide a detailed analysis of a topic.
-Can provide background information early in the research process.
-Overview of big issue or quick authoritative answers (reference).
-Contain bibliographies that can point you to other source
The NIST site to the left probably contains links to articles that explain how to measure the constants, but you may find it hard to navigate. Another resource you can try is the American Journal of Physics, which is aimed at undergraduate education, and often contains articles that explain how to do interesting experiments simply and cheaply. The Physics Teacher is aimed more at High School and introductory physics, but often has neat ideas for experiments and demonstrations. Try searching through their archives with words related to your constant.
Another great place to look is university course home pages. Many schools have developed labs to measure these constants, and sometimes you can find on-line lab manuals. You could also check the catalogs for such companies as Vernier, TeachSpin, and Pasco, to see if they have ready-made equipment to measure your constant. Be careful about citations! Lab manuals are usually not sufficient for citable sources -- find redundant print sources. A few university links are below. See the course web page for other examples.
This is a search engine specifically oriented around academic journals. Once you have a constant you want to research, you can probably find guides on how to measure it here.
The following databases will help you find articles.
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