This is a favorite website of mine for finding just the perfect classroom activity!
FREE Teaching Resources for Your Classroom
Dear Educator,
I am writing to tell you about www.Curriki.org–a website for teachers that includes free access to over 32,000 K-12 high quality lessons, units, assessments and multimedia learning objects.
All of the resources on Curriki are contributed by teachers, universities, publishers and education professional development organizations from around the world. Furthermore, content is reviewed by subject-area experts and members to ensure quality.
via Spread the Word: Free Educational Resources « Curriki’s Blog.
RuthK MakerSpace 
Thank you so much for sharing Curriki with your personal learning Network.
I would love to learn how you are using Curriki and what resources you find particularly useful.
I welcome you to contact us @Curriki on Twitter or on our blog: http://blog.curriki.org
Sincerely,
Anna
Curriki International Consultant