I'm trying to figure out the title of a book I read as a child -- probably around 1988 -- aimed at 9-10 year olds. The story had to do with people leaving Earth and they were only able to take one personal item with them each. I remember one person bringing a biology book -- which was helpful. When they arrived at the new planet, there was glass-like grass that burned funny colors and strange stones around that turned out to be eggs for some beautiful moth-like creatures. If it helps, this was a reading assignment given to me in the 5th grade in the United States. Any ideas on what book this might have been?