Elf is a classic Christmas movie that can be enjoyed by people of all ages, including 6-year-olds. It is a heartwarming and funny story that teaches the importance of kindness, compassion, and acceptance. The movie features many silly and entertaining moments, making it a great choice for children who are starting to understand the true meaning of Christmas. However, as with any movie, parents should use their own discretion when deciding if it's appropriate for their child, and it's always a good idea to watch it with them so you can discuss any questions or concerns they may have.