I usually find that encyclopedias are great resources for quick facts like these about civilizations. I checked the MSN Encarta online encyclopedia (encarta.msn.com) and found the following that should help by selecting their Multimedia links in the entries for the Maya Civilization and Aztec Empire:

Map of Maya Civilization:

http://encarta.msn.com/media_461531201_761576077_-1_1/Maya_Civilization.html

which notes “The Maya civilization encompassed all of the Yucatán Peninsula in present-day Mexico and parts of present-day Guatemala, Honduras, and El Salvador.”

Map of Aztec Empire:

http://encarta.msn.com/media_461517561_761593151_-1_1/Aztec_Empire.html

which notes “The Aztec created an empire in the 1400s in the region that is now Mexico. Their capital, Tenochtitlán, stood on the site of present-day Mexico City.”

To compare with modern day Mexico to see what other cities/areas were included in those shaded areas, check out this page for some maps of Mexico:

http://www.factmonster.com/atlas/mexico.html

I hope this answers your question,

LibrarianPM

p.s. Local libraries are also great options for homework help! Find your local library online (you may be able to chat with or email their staff) at:

http://lists.webjunction.org/libweb/