The History of the Earth: Supplemental Guide CA | Culminating Activities 173Same Rocks, Diff erent Sort
Materials: [from Lesson 5] four small/medium-sized rocks
of different types per group, a few extra rocks for
samples, six small bins, boxes or containers, index
cards with labels, markers, tape, one copy per
group of Instructional Master 5B-3.
Advance preparation: Remove the cards from the sorting bins,
and then select six different description words from the class’s
Rocks Book. Write one word on each card, add a small supporting
illustration to help students remember what is written on the card,
and then attach each card to a bin. Place the bins around the
classroom.
Divide students into groups of four. Give each group four small/
medium rocks of different types. Explain to students that they
are going to sort rocks again but will use different characteristics
to group the rocks. Walk around the room, and read the bin
labels with the students. Explain to students that you are going
to name a characteristic on one of the bins. Tell students that if
they have a rock that matches that characteristic, they should
raise it into the air. Confi rm that all raised rocks match the named
characteristic,and then have student place their rocks into the
appropriate bin. Continue this process until all the rocks have been
sorted into various bins.
Assign one bin to each group. Have students use Instructional
Master 5B-3 to organize their rocks along the horizontal
comparison line from those rocks that most demonstrate the
characteristic identifi ed to those that least demonstrate the
characteristic. Have each group present their comparison chart to
another group.Letter to a Geologist or a Paleontologist
As a class, brainstorm ideas and then write a letter to Gerry the
Geologist, Pam the Paleontologist, or to a real scientist. The
students might want to write about what they have learned about
those professions or ask questions they may still have about the
history of the earth.