Dictionary.com

"Dictionary.com is the world’s leading online source for English definitions, synonyms, word origins, audio pronunciations, example sentences, slang phrases, idioms, word games, legal and medical terms, Word of the Day and more."

Fact Monster

Flashcard Stash

"The easiest and most fun way to study!"

Google Scholar

"Comprehensive, user-friendly, and free, Google Scholar is an excellent tool for high school students who are getting their first taste of academic research. Search listings also include links for "related articles" and "cited by," two features that may help users expand or narrow down their inquiry. Combining the ease of a search engine with the quality and reliability of a library, Google Scholar blends the best features of both worlds."

Khan Academy

Snappy Words

Snappy Words is "an online interactive English dictionary and thesaurus that helps you find the meanings of words and draw connections to associated words. You can easily see the meaning of each by simply placing the mouse cursor over it."

Wordsmyth