Summer Research Program for Science Teachers

Kiran Purohit

Manhattan Academy of Technology

Piecing together the Geological History of the NYC Region

8th grade Earth Science



This activity (which actually takes a few days) fits in with a unit in which students are learning about the geological history of NYC and this region. It builds on field work students should have done earlier in the unit, collecting observations of the rock formations in Manhattan and possibly in places outside of Manhattan. Some good places to do field work might include: Central Park’s outcroppings of bedrock, the cliffs at the Palisades in New Jersey, the rock in Inwood Park, and the beaches at Coney Island or other parts of Brooklyn.


If it is really not possible for students to go to any of these places, then it is worth considering just getting pictures. There are actually many, many online sources that have images of the rock formations around the city. You can use these in class, and it might work in place of doing real field work (although field work is definitely preferable!)


In any case, students should have opportunities to observe examples of the following before doing this activity:

· glaciation and glacial action

· metamorphic rocks—foliation, crystal formation

· rock layers that have been folded

· outcroppings of different kinds of bedrock

[CONTENT STANDARD D: As a result of their activities in grades 5-8, all students should develop an understanding of

o Structure of the earth system

o Earth's history

o Earth in the solar system]

In the course of this activity it should be possible for students to put together all the different pieces of information they have learned, as well as information from other scientific sources, to construct a coherent explanation of how the geology of this region was constructed over time.


The pacing of this activity will (of course) vary depending on the kind of time you have in class periods. In this overview it’s divided into Part 1, Part 2, etc., and you can schedule those parts any way you like.


Finally, if you want more information, including examples of how students have solved this problem, you can email me at I would rather not put student work on this website, because it takes some of the challenge out of the activity for future groups of students!






· Have students put together all the data they have learned about NYC’s geology, in a form that reflects the way the steps are connected.

· Discuss the uses of fieldwork, and how this kind of data collection can be used in conjunction with other kinds of data.

· Facilitate student communication about material they have gathered from fieldwork, notes, science articles, and the knowledge of other students.

· Work on students’ understanding of change over time as a gradual geological process in which different events take different amounts of time.



Part One: Introduction


Give out the handout (Activity Description) for this activity, and have the students sketch out their initial ideas, working in groups (3-4 people per groups is best). How you organize this introductory part of the lesson depends on the dynamics of the class and how accustomed students are to working in groups. It is a good opportunity to get a sense of how well the students understand the connections in the material, and how much help different groups are going to need to piece this together!




Part Two: Stations


How you decide to set up these stations has a lot to do with the kinds of experiences your students have with doing work in stations. The basic idea behind organizing stations is that students are getting information from a variety of sources and trying to piece it together for solving a larger problem or making sense of a larger phenomenon. Here are some guidelines to consider when doing stations:


· You may need to set specific amounts of time for each station, so that people share the materials and the activities fairly. On the other hand, you may be able simply to have the stations available, and people can come and go as they wish.

· You should set up a place for students to take notes, either in the form of a handout on the stations, or in their science notebooks/journals.

· You should allow time for people to go back to stations.

· You should have enough materials that no-one feels cheated out of doing a fun station. If this might be a problem, schedule the turn-taking so everyone feels that it is fair.


1) Rock observations

-    Provide several rock samples. These should be a typical assortment of different types of rocks you might get with an earth science kit.

-    Make sure the samples are labeled correctly. This is not supposed to be a guessing game or a scavenger hunt.

-    When groups come to the station, have them focus on finding rocks that are similar to the ones they saw at the Palisades, at Central Park, etc. Specifically, have them focus on the color, mineral size, texture, and foliation. You can also have them look at density, but only if they have learned something about density before doing this station.

-    If students are really clear on what they are doing in this whole activity, you can just let them look at the rocks, take notes, and piece things together on their own. If they are not really getting the big picture, you might want to give a worksheet to guide their thinking, so they can get organized.


o The solid earth is layered with a lithosphere; hot, convecting mantle; and dense, metallic core.

o Lithospheric plates on the scales of continents and oceans constantly move at rates of centimeters per year in response to movements in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, result from these plate motions

o Land forms are the result of a combination of constructive and destructive forces. Constructive forces include crustal deformation, volcanic eruption, and deposition of sediment, while destructive forces include weathering and erosion.

o Some changes in the solid earth can be described as the "rock cycle." Old rocks at the earth's surface weather, forming sediments that are buried, then compacted, heated, and often recrystallized into new rock. Eventually, those new rocks may be brought to the surface by the forces that drive plate motions, and the rock cycle continues.]


2) Rock Layers’ Folding

-    Provide modeling clay or dough that students can put into layers.

-    Have them figure out a way to show the formation of the folded rock they saw in one of the fieldwork sites—probably Central Park. Basically, this is a modeling activity, so students probably would need some time to figure it all out.

-    If putting together the model with little guidance is too hard, or if it will turn into a major activity of its own, you might want to have students do an activity on one of these pages, then relate it back to the activity:


3) Reference Books and Field Guides

-    Provide several reference books about rocks/minerals and geological history.

-    Make sure that at least some of the books give enough information on the kinds of rocks students will need to know about.

-    If your school doesn’t have much in the way of reference books and trade books on this topic, consider printing websites and keeping them in file folders for students to refer to.

-    If students need more direction, get them to consider:

· how deep in the earth certain rocks had to be in order to form

· how long they might have taken to form

· what materials they had to have been made from

· what all of this tells you about this region back when the rocks formed




Part Three: Online Discussions


[This could also be a discussion in class, but it’s a good opportunity to incorporate computer-based work.]


Online discussions are a good way to include the input and ideas of people who might not normally manage to speak up in class, but who nonetheless have things to say and ideas to contribute. It also allows the time for people to read the work of other people, rather than being forced to respond quickly, the way classroom discussions require them to.


A good site to use for setting up a pretty inexpensive bulletin board, with no advertising and no needed experience with programming boards, is


There are two online discussion assignments that make sense with this activity. If you have a 4-computer set-up in the classroom, as many NYC classrooms do, you might want to consider doing one or both of these discussions as a station during Part Two.


1)  After doing the stations in class, please have one person in your group write up a description of what you did in the station. The comments you post on the bulletin board should explain what you did, what you found out, and how this relates to the overall activity we are doing. The other two or three members of your group also should post something to the board, but they should post a reply to another group’s work. The idea is to get a discussion going!

2)  Go online and find a website that provides information about the geology of the NY region. Read over the website and make sure that it is at a level that could be understood by people in the class! Then post a review of this website on the bulletin board. Explain how the site relates to the activity we are doing, and provide a link to the site.




Part Four: Working on Diagrams to Present to the Class


At this point, have the students go back to the first handout, the Activity Description. They just need to piece all the part of the problem together and come up with some kind of visual representation of what they figured out.


The major thing here is that students need to understand that all the steps fit together in different ways. So if they have places missing in the sequence, they should try to fill it in with some plausible explanation.


You can have them do the diagrams on chart paper or overhead transparencies, depending on how you want to do the presentations. You could also have them create diagrams using a program like Inspiration, then present to the class using a computer projector, but obviously this is only a good idea if there are enough computers for everyone to complete their diagrams in this way.


As groups work on diagrams, the teacher should go around and talk with them. I think this activity works best when it is presented as a puzzle, like a problem everyone is trying to figure out. It doesn’t need to get competitive, but you also don’t want too much discussion between groups at this stage, or their work will all end up looking pretty similar. So maintain a little bit of secrecy. I also allow each group just 3 major questions for me. Sometimes I ask that they write out these questions before asking them, so that I can be sure they have really thought through what they are trying to figure out. This doesn’t mean that I will not talk to them outside of the three questions, but I try to avoid talking people through the whole problem!

[Content Standard A: Science as Inquiry. COMMUNICATE SCIENTIFIC PROCEDURES AND EXPLANATIONS. With practice, students should become competent at communicating experimental methods, following instructions, describing observations, summarizing the results of other groups, and telling other students about investigations and explanations.]


Part Five: Diagram Presentations and Discussion


Have each group present their work and explain the information they got and how they pieced it together.


This is the time for the class as a whole to synthesize all the different material. It is a good idea to post a few pieces of chart paper, and as the presentations go along, have a student keep notes on each topic. Some topics for the charts might include:

· Processes that can happen to rocks

· Types of rocks and how we identify them

· Major geological events that have occurred in this region

· Evidence we examine to figure out geological history

You can pick other topics for the charts, of course.


The discussions should provide the opportunity for students to critique each others’ work, clear up confusions and misconceptions, and fill in the gaps in the information they already have on their own diagrams.

[Content Standard A: Science as Inquiry

RECOGNIZE AND ANALYZE ALTERNATIVE EXPLANATIONS AND PREDICTIONS. Students should develop the ability to listen to and respect the explanations proposed by other students. They should remain open to and acknowledge different ideas and explanations, be able to accept the skepticism of others, and consider alternative explanations.]





Really any part of this assignment could be homework. It really depends on how you pace this activity. Here are some more specific homework ideas, though:

· Write an explanation of each of the stations you did today. Explain how each one relates to the activity we are working on, and how it is going to help you solve the puzzle.

· Do one of the bulletin board assignments as homework.

· Write a final report on this activity, including citations of different books and materials you referred to, explaining how the NYC region formed geologically. Explain all the major geological events, and how these are connected to what we see today.




Activity Description: Piecing together our Geological History



Over the next few days, you are going to work as a group to figure out, based on different kinds of evidence, the geological history of this region. Your task is to create a diagram that shows through pictures (and some text) all the processes that happened over time. Your diagram might end up looking like a flowchart, a timeline, or something else…but it has to show as many steps as you can figure out.


Deadline: ______________

We will have time on this day for groups to present their diagrams. You should plan to use either a chart paper, a set of overheads you create, or a computer-based presentation. Whatever you choose, it has to be ready by the deadline. No technical problems allowed!



Getting Started


With your group, please start off by writing out as many of the steps as you know already about NYC’s geological history. These don’t have to be in order, and you don’t have to agree on all of them. Just start writing them. You can use the space below, or go on the back.













Asking Questions


You can ask me questions as you work along, but I really want to make sure you have time to think through what you are doing and ask thoughtful questions. So, you get three questions. Please write them out in the spaces below before asking them, and let me know when you are ready to talk!








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