magazine has been continuously published since 1978, we are publishing some of the articles from the archives for historical interest, such as this.
This activity on determining age of rocks and fossils is intended for 8th or 9th grade students.
In this activity, students begin a sequencing activity with familiar items letters written on cards.
Once they are able to manipulate the cards into the correct sequence, they are asked to do a similar sequencing activity using fossil pictures printed on "rock layer" cards.
Students should be able to understand the principles and have that as a background so that age determinations by paleontologists and geologists don't seem like black magic. Geologists in the late 18th and early 19th century studied rock layers and the fossils in them to determine relative age.
William Smith was one of the most important scientists from this time who helped to develop knowledge of the succession of different fossils by studying their distribution through the sequence of sedimentary rocks in southern England.
Time factors of millions and billions of years is difficult even for adults to comprehend.