Westward Expansion : 
Try the Phoenix Library site above for books online and to have books sent to the nearest branch.
General/overall sites:
"Moving West", "On the Oregon Trail", "students' perspectives of the trail", "history of Oregon Trail" or "Emigrant Road" (with photos and maps)
The Trails
http://library.thinkquest.org/CR0210182/route.html
Also, try the general sites above
Forts
http://library.thinkquest.org/CR0210182/forts.html
Also, try the sites for landmarks.
Landmarks
"PBS OT sites"
http://library.thinkquest.org/CR0210182/landmarks.html
http://www.isu.edu/~trinmich/Sites.html
http://www.nps.gov/whmi/educate/ortrtg/1or0.htm
http://www.beavton.k12.or.us/greenway/leahy/ot/landmarks.htm (A kids' version:) and http://www.beavton.k12.or.us/greenway/leahy/ot/research_l.htm sites
http://www.emigrantroad.com/contents.html (to visit the sites by photos and maps)http://flms.ddouglas.k12.or.us/~ludwig/tag/thinkquest/Oregon_Trail/1trtr.thml
Try the "Landmark Challenge"
Wagons
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/wagontrain.htm http://library.thinkquest.org/CR0210182/inwagon.htm
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/wagons.htm
http://www.sover.net/~barback/ot/wagons.html (Different kinds of covered wagons)
http://endoftheoregontrail.org/wagons.html Prairie Schooners
http://204.234.22.1/SDGI/Newell/Blueprint.html Blueprint of a Wagon, supplies, etc.
Animals
http://library.thinkquest.org/CR0210182/livestock.html http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/oxen.htm
http://heritage.uen.org/cgi-bin/websql/query.hts?type=6&tid=50814
Supplies
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/weapons.htm http://library.thinkquest.org/CR0210182/supplies.html
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/food.htm
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/tools.htm
http://204.234.22.1/SDGI/Newell/Supplies.html
Pioneer Life in General
http://www.geocities.com/Heartland/Valley/6470/
Clothing
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/clothing.htm
http://library.thinkquest.org/CR0210182/clothing.html
http://www.saskschools.ca/~gregory/settlers3.html scroll down to spinning and weaving and clothing
Cooking
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/cooking.htm
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/fires.htm
http://www.lapcohistsoc.org/cooking.htm
Kids on the Trail
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/children.htm
http://www.or.blm.gov/nhotic/Kids/trailkids.htm
http://heritage.uen.org/cgi-bin/websql/query.hts?type=6&tid=48
Mountainmen
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/mountainmen.htm
Native Americans
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/nativeamericans.htm
Hardships
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/rivercrossings.htmhttp://library.thinkquest.org/CR0210182/hardships.html
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/hazards.htm
http://www.cob.montevallo.edu/O'TooleTK/
Chores
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/chores.htm
http://www.saskschools.ca/~gregory/settlers3.html
http://fayette.k12.in.us/frazee/Pioneer_Life.html
Diseases
http://www.beavton.k12.or.us/greenway/leahy/ot/guidebook/sickness.htm Danger on the Trail
Weather
http://library.thinkquest.org/CR0210182/weather.html
Mistakes
http://library.thinkquest.org/CR0210182/hardships.html#nono
Games and crafts
Oregon Trail Guidebook-Crafts
Pioneer Games
http://heritage.uen.org/cgi-bin/websql/query.hts?type=6&tid=50782