As promised, here are some more fun things to do with envelopes. The outside of the envelope often has lovely boxes of lines under the stamp area or else they bear an interesting postmark. Here I have simply taken some of the wavy lines, straight lines and interior patterned papers--cut them out--and lined them up as packages. Then, they have been topped them with bows. (Wouldn't these packages make for a cute front of a birthday card?) Teachers might want students to count the lines and put the numeral under the package. Maybe these shapes could be buildings instead of packages. Or, perhaps several could be combined to make "blocks" for building. It is advisable to cut (or have students cut) some of the patterns from the outside of the envelope and collect them in a clear plastic bag ahead of time so that there are plenty of pieces available when you begin this activity. Or, have a lot of envelopes available for students to choose and share shapes. Have fun!