Although the first two sites are not lesson plans...I do believe that the political cartoons posted at the sites provide some interesting and valuable lessons in history as seen through the eyes of Dr. Seuss...

• Catalog of Political Cartoons by Dr. Seuss - when we hear the name Dr. Seuss our thoughts immediately gravitate to children's books, but for the fact is Dr. Seuss penned over 400 political cartoons for the New York newspaper PM from 1941-194. Students 9-12 can view over 350 of those cartoons when they visit this site.
• The Political Dr. Seuss - PBS has posted an interesting site based on Theodore's political cartoons. Don't miss the lesson plans found at the For Educators link.

The following lesson plan sites are more traditional...

• A-Z Stuff Teacher Stuff: Dr. Seuss Activities - the site includes cross-curricular activities for 15 Dr. Seuss books that would be appropriate for students in grades K-2.
• Lesson Plans Page.com: Initial and Final Sounds With Dr. Seuss' Hop on Pop
• Hop on Pop Ideas - a lesson found at Teaching is a Work of Art
• Cat in the Hat - a mini unit found at Teaching is a Work of Art
• Hooray for Diffendoofer Day - several ideas for lessons found at Teaching is a Work of Art
• A Dr. Seuss Booktable- ideas and books posted by an Elementary teacher
• Dr. Seuss Activities, Printables, Lessons - several interesting ideas posted by a teacher, Michelle Hubbard
• Teaching Short Vowel Discrimination Using Dr. Seuss Rhymes - posted at the Read*Write*Think site this lesson is appropriate for K-2 students
• Reading Everywhere with Dr. Seuss - this lesson is also posted at the Read*Write+Think site and is appropriate for K-2 students