Make your newsletter in a word processor program with a headline and columns. Insert images and text boxes as needed. A two-page newsletter printed on both sides of the paper works great. Send the paper to family and friends.
Have the kids brainstorm ideas for columns to include. During the school year, you can include pieces they've written as assignments. The summer editions can include trip journals and accounts of other family fun.
Here is a sample newsletter and some suggested columns for the front page to get you started. Print the sample newsletter to show the kids and get them excited about creating their own newsletter.