Do they want to know the whole truth?

As the keeper of the family history, which I have spent about 20 years of leisure time collating; I would like to pass on the information contained in several crates and boxes in a form which my grandchildren will find interesting. I thought I might start with my autobiography because I have always wondered about my own grandparents lives. Where did they go to school? What did they eat or play? Who were their friends? Inevitably there will be events, even in my history that would surprise them . How do you make it interesting but not shocking?