42eXplore: 100th Day
http://www.42explore.com/100day.htm

100th Day of School - A to Z Themes
http://www.atozteacherstuff.com/themes/100days.shtml

Mrs. Bromley's Kindergarten: 100 Days
http://www.onekama.k12.mi.us/e2003/kdgb/February/100Days.htm