Do Your Own Dig

Part of the Petra exhibition.

Time required: 3 or more periods

Age level: grades 6-12

Note: This activity requires teacher or other adult supervision. Please review in advance the "Do's and Don'ts" listed at the bottom of this activity.

This calls upon students to use mathematical skills and scientific inquiry to generate and process information from their own excavation site. Archaeologists learn about the past by studying the remains of things that people have left behind or thrown away. Over time these remains get buried beneath layers of dirt and debris, so recovering them means digging into the ground. This is called a "dig" or an "excavation", and the location is called a "site." A dig is a carefully planned and highly organized investigation. Archaeologists use a variety of tools to excavate a site. You can use household materials to assemble your own version of an archaeologist's tool kit.

Tools for Setting Up the Dig Site:

  • a measuring stick or tape at least 50 centimeters long (1 meter = 39.37 inches, so 50 centimeters = 19.69 inches)
  • a ball of string
  • protractor
  • large nails (or small stakes)
  • a small hammer to hammer in the nails or stakes

Tools for Digging:

  • a small shovel or scoop for removing topsoil
  • a sieve or screen with a mesh no finer than about 5 mm to sift dirt (See "Make Your Own Sifting Screen" activity)
  • a garden trowel or spatula for uncovering artifacts
  • small paintbrushes or toothbrushes for removing the last bits of dirt

Tools for Recording Data:

  • a notebook
  • graph paper
  • small plastic bags
  • tags or stickers to label the bags
  • aluminum foil
  • camera

Getting Ready to Dig

Choose an area that looks as though it might contain man-made objects, perhaps where a brick shows on the surface, or where you've found coins or bottle caps. If it's on private land, ask permission to dig from the owners; if it's in a park or empty lot, obtain permission from neighborhood officials.

  1. Using your measuring stick, measure out 4 lengths of string at least 70 centimeters long. Mark out 50 centimeters on each piece, leaving extra string on both ends so you have room to tie it to the nails.
  2. Lay the strings on the ground, to form a square over the site where you want to dig. At each corner of the square, join two strings at their 50-centimeter marks by tying them together around one of the nails (repeat this 4 times).
  3. Hammer in one nail and then a second one, making sure that string between the two nails is pulled taut.
  4. Place the third nail so that the line of string forms a right angle with the string already hammered into place. Use the protractor to make sure the angle is exactly 90 degrees; then hammer the third nail in into the ground.
  5. To set the last corner of the square, pull the fourth nail until both strings are taut and hammer it in.

Digging and Recording your Finds

Now you're ready to begin digging. Archaeologists dig in levels - called stratigraphic levels because they relate to layers of soil deposition - which helps them keep artifacts from the same period together. Sometimes differences in the color or texture of the earth define the levels. Or, if all the soil is the same color and texture, archaeologists might establish a new level at a given interval, perhaps every 10 or 20 centimeters. Each level is assigned a number. Archaeologists record the provenience, or information about each level-in a form or in a notebook.

1. Use your shovel and trowel to remove the topsoil or grass with care. Usually this is the root zone for small plants and grass, which is about 5-10 cm deep. Caution should be taken to work around tree roots. Do not cut them. This is Level 1.

2. Did you find anything? If so, take pictures of each artifact before fully excavating it. The pictures are to help you later in the lab, so take as many as necessary in order to record all valuable information: the scale of the artifact (place a ruler or other item of readily identifiable size, like a coin, next to it to establish the scale), the relationship between the artifact and another one, and its location within the site.

3. Draw the artifacts you uncover on graph paper. For an 8/5 x 11 inch sheet of paper, a scale of 1:20 cm works well. You can use measuring tape or rulers to help you plot the location of each object within the square. In order to record the location of your artifacts on graph paper and then draw them to scale, place your measuring tool along the edge of the pit. Use another ruler to measure the location of the artifact relative to the edges of the pit. Then, treating the edges of the pit as the X and Y axis on your graph paper, record this information on your graph paper (after reducing the lengths by the appropriate scale, in this case 1:20).

4. Pass the dirt through your screen to make sure you don't miss any small pieces.

5. Create a Provenience Card for each level excavated, by recording the following information:

Stratigraphic level: (Level 1, Level 2, etc.)
Soil characteristics: (What does the soil look like? What does it feel like? For example, is it brown and moist and coarse-grained? Or light colored and sandy?)
Thickness of the level:
Relationship to other levels or objects found: 
Recovery technique: (screened or not screened)
Material: (1 bag of shards, 1 bag of bottle caps etc.)

6. Archaeologists typically save all the same kinds of artifacts from the same level together in one bag. This helps organize the material back in the lab. Place all objects found at this point in this bag. On the label, record the following information:

Stratigraphic level:

7. After removing Level 1, begin a new level by using your digging tools to slowly remove a thin layer of dirt. Dig to a depth of about 10cm, or until you hit artifacts, whichever comes first. Ideally you want to dig around the artifacts and leave them in place until you uncover roughly the same depth throughout the pit. In this way you can draw and photograph the artifacts in place before you take them out. This is Level 2. If the artifact appears to "reside" in more than one level, keep it in place and excavate the next level before removing the artifact.

Archaeologists repeat this process of excavation - digging, recording levels through photos, drawing, and grouping and labeling artifacts for lab work - until they can't find anything anymore, until they hit bedrock, or until the pit is too deep to get into and excavate. For this activity, you can determine a set number of levels to excavate.

Laboratory Observations and Analysis:

1. Once the excavation is over, it's time to analyze your objects, notes, and drawings. You might want to gently wash any non-perishable items like pottery, glass, coins, or plastic. Don't wash anything that looks too fragile or objects that might disintegrate in water, like plant or animal remains or pieces of cloth.

2. Study each object for details that weren't visible in the field. In your notebook, describe the attributes - things like size (length, width, thickness), color, weight, shape, composition (glass, plastic, metal), and decoration - of each object. What do these things tell you? Do they help you determine where the artifact was made or how old it is?

3. Next, group the artifacts found on each level together and examine them accordingly. (Your drawings and photos will remind you where each was found.) How many different kinds of objects did you find in each level? Are they the made of the same kinds of materials? Could any fragments have come from the same object? If so, can you glue them together? Do you think the artifacts you found together were made in the same place? Do they come from different states? Different countries? Do you think some artifacts are older than others? Why do you think you found these artifacts together?

Do's and Don'ts When Digging

  • Make sure that you plan to dig in a place where you have received prior permission.
  • Make sure you dig under adult supervision.
  • Contact a city or state archaeologist if you find something that appears to be a significant artifact.
  • Be prepared to spend a lot of time looking. Digging and collecting data can take lots of time and patience, but what you may find is worth the wait!
  • Wrap any sharp or fragile artifacts in aluminum foil to protect them and protect yourself. You may choose to wear gloves.
  • Make sure you fill in the excavation area once you're finished digging.


  • Never go digging alone.
  • Never climb into dangerous areas.
  • Never touch animals that you think could be poisonous.
  • Never dig too close to a tree, because you could damage the roots.

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