Grades 4-6. 25 exciting Mysteries & complete teacher information in Spanish. Rock Detective Bucket Kits include everything you need for a class of 30 students: 25 "mysteries" 35+ sample rocks, fossils and minerals. As students investigate and solve the "mysteries" contained in the Rock Detective Kits, they will discover for themselves a multitude of earth science concepts. The freedom to move from desk to desk and to share ideas greatly enhances the learning experience. Rock Detective Mysteries exceed the National Science Council's recommended Content Standards for National Science Education.