Unfortunately, I don't have a colored printer (only B&W images shown above), but all of the centers are full-colored. There are 5 math centers and 5 literacy centers. Check out all the details here.
I always would use centers like these (ones that review skills students most likely already have) at the beginning of the year while I teach my students the routines and procedures about rotating in centers in my classroom. The skills in these centers are most appropriate for grades 3 and 4 and should be able to be completed by the students with minimal support.
Oh yeah, did you check out these FREE math centers I posted about a little while ago? You should snag those, too! They're prefect for teaching about using math manipulatives!
Do you use centers in your classroom? How often do you change them up?