This is a perfect idea for letters to parents as well as thank you notes. These would also be good in the writing center to encourage children to write to their friends.
Cut paper into fourths and give each child a section. Ask them to draw their picture and write their name with a black marker. Reduce their drawings and glue around the edge of a sheet of paper. Make LOTS of copies on white paper or colored paper.
*To make note cards glue pictures to the bottom half of a sheet of paper. Run off on card stock and fold in half.