new here and jumping in!
This blog post might be helpful: http://wearethatfamily.com/2011/06/preparing-your-kids-for-global-missions/ .
We are also hoping to have a missions focus in our homeschool, and are planning to use many of the above mentioned resources, namely Missionary Stories with the Millers, I Heard Good News Today (Sonlight, Core A), and YWAM Heros for Young Readers. Our family has a heart for Uganda, and will be travelling there this winter, therefore, we are focusing on the YWAM stories where the missionaries served in Africa, as well, as learning more about Uganda the country. Books like Beatrice's Goat, Give a Goat, and One Hen are helpful in showing how people in other countries can be empowered by the aid they receive. If your family has a heart for a certain nation, maybe you could apply these ideas. The book Operation World has prayer guides for many different nations.
Another book that has a lot of ideas is, The Mission-Minded Family.
HTH,
Julie