Lynn (TheLankyYankee) - reviewed Themes Bulletin Boards Across the Curriculum: Ready-To-Use Activities Projects for the Elementary Classroom on + 81 more book reviews
Over 300 pages with ideas for themes, including each season, families, circus, bears, farms, habitat, undersea, ecology, and global carnival. Includes a book list for each theme. Many of the activities can be modified for different subjects and the skill level of your students. IMO the ideas are best for grades 1-3.