First of all, we need to determine what style of citation you are using. Is it MLA or APA? Most likely, being in 10th grade and an English class, you are using MLA.
Next, we need to treat the source as a chapter from a book, or an article from a book.
If you have Microsoft Word 2007 or later, there is a reference tab you can use. Go to the tab that says REFERENCES. Look for the style button and click the appropriate style (MLA or APA) Then click on INSERT CITATION. Click ADD NEW SOURCE. A new screen will open. If you are in MLA format, use the pull down field to click on BOOK SECTION. Fill the information in accordingly. Click on OK. Next, go back up to the top and click on BIBILIOGRAPHY. One more time, select either a BIBLIOGRAPHY or WORKS CITED list, and it will put the entry together for you.
Another worthwhile resource is the OWL at Purdue. It is short for the Online Writing Lab.