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Beyond the Book
Project 3B- Grinding Corn

In the Book
In Mayeros, there is a picture of Doña Satulina and Adela grinding corn into flour in order to make tortillas (pp. 5, 7). The device they are using is called a metate and has been used by native cultures throughout North America to grind corn into meal and flour as well as for grinding herbs and spices for cooking and medicinal purposes. (The Pueblo Indians of New Mexico, for example, used this very simple machine.)

The author explains that nowadays women usually bring their corn to a mill to be ground (p. 6). Note that in the picture, the women are adding water to the grinder in order to make a paste or dough (called pozole), rather than make dry cornmeal.

Beyond the Book
There are two activities included here: one for making cornmeal and the other for making masa, or corn dough. If students complete both activities, they can also make some comparisons between the two processes. From either activity, students will learn the amount of work involved in making cornmeal or corn dough. These experiments prompt students to reflection upon: how much corn it would take to make one tortilla, how many tortillas each person in a family might consume at a given meal (considering it is the only bread available, etc.), and therefore how many tortillas are consumed over the course of a day. The Grinding Corn Worksheet provides some questions that serve as a starting point. Teachers will come up with many creative ways to continue this cultural math lesson.

The teacher can provide a sample bread recipe for comparison and discuss other grains, meals available to people in other regions of the world. Other cultures have potato pancakes, rye bread or rice as a staple. Through these discussions, students will come to understand the importance of corn to both the historical and modern Maya and the impact of different crops and packaged foods on local cultures. They can then explore how their eating habits are different now than if they could only eat what is available locally.

Materials
On-line:
Grinding Corn Worksheet

Required for cornmeal:
An ear of corn
Measuring cup
Dried whole corn for each student or group of students
Metate, mortar and pestle or other manual means of grinding corn
Warm water
Salt
Waxed paper
Rolling pin

Suggested for cornmeal:
Hand crank coffee grinder
Tortilla press
Store bought corn flour (Masa Harina)

Required for corn dough:
An ear of corn
Canned whole hominy
Metate, mortar and pestle or other manual means of grinding corn
Measuring cup
Warm water
Salt
Waxed paper
Rolling pin

Suggested for corn dough:
Towels (for clean-up)
Food processor
Tortilla press
Store bought corn flour (Masa Harina)

Activity Suggestions
1. Calculate the number of kernels on an ear of corn (approximate)
2. Supply enough dried whole corn and grinding “machines” (mortar and pestle or metate y mano – grinding stone) for the class to work individually or in groups. Make note of what fraction of an ear of corn they each have to work with.
3. Measure and then distribute an equal amount of corn for each student or group.
4. Have students pulverize the corn using the grinding “machine” until it is as fine a meal as they can get it.
5. Time how long it takes to reduce the whole corn to ground corn.
6. Measure the yield of each group for the discussion and calculations on the Grinding Corn Worksheet.

Making Connections
Students can set up a corn grinding/hominy mashing station. This is an easy way to incorporate math and science into a cultural lesson or display. Visitors can try their hand at grinding corn and then see the sample calculations the students made in their own experiment. Students can substitute the visitors’ grinding time, recalculate, and provide information to each visitor. There can also be a display with substitutions of tortillas per slice of bread or bread product and visitors can learn how much time they would have to spend grinding corn in order to meet their bread-consumption demands on a daily or weekly basis.

Students can prepare tortillas for sale or display using packaged corn (not flour) tortillas or make tortillas using store bought corn meal. This is available at specialty food stores, the international aisle at the local supermarket, or at a variety of sites on-line.