1. In preparation for today’s class, write the following
instructions on the board: “With the information you
have gathered about arsenic and its effects on human health,
create a diagram or chart in which you display this information.
Include in your chart the following information:
a) What is arsenic? Describe its nature, qualities, origin,
b) Where does arsenic occur in our environment?
c) How can humans come in contact with arsenic?
d) List various ways that arsenic can harm human health.
This starter activity will allow students to explain what they
know about arsenic in detail, focusing on the main questions
they will have to answer for their final projects.
2. As students enter the classroom, have them complete the
starter exercise. Give students about ten minutes to gather
data from their notes, and compose it into a flow chart, bar
chart, or a diagram of their choice. Tell students to present
the data in a way that is easy for them to understand. You
may want to allow students to then share their data with a
partner, or discuss it as a whole class briefly, to see if
their information is consistent across the class.
3. After students have reviewed what they know about arsenic,
have a brief class discussion. Ask the class this question:
How does arsenic compare to other common water contaminants?
Is it more toxic? Less toxic? How is this determined? Which
is easy to remove from water, which is more difficult? You
may want use Venn diagrams (on paper or on the board) to compare
arsenic to several other water contaminants, such as lead,
pesticides, nitrates, etc. Remind the class that this data
will help them create a persuasive context in which to write
about the dangers of arsenic. Discuss the various resources
which students discover. Which resources are the most useful?
What makes them so? Who is the intended audience of these resources?
How can you tell?
4. Spend the remainder of class (about 30 minutes) formulating
a rough draft response to the following question: “How
does arsenic affect the population you have studied? Consider
three aspects: the environmental, the human health, and cultural
implications of this contamination.” Students will use
their data and notes as the brainstorming stage of the writing
process, and begin to compose a rough essay answering the prompt.
Allow students class time to begin their rough
drafts, or you may spend the time reviewing essay composition,
including thesis writing, topic sentences, paragraph organization,
introductions, conclusion, etc. This portion of class can be
adjusted according to the ability level of your students.
Assessment can happen at various stages, depending on
your class needs. The teacher should look at student responses
to the starter prompt and ensure that arsenic information
presented on charts is consistent. During discussion, check
to see if students can successfully compare and contrast
two topics. Finally, the rough draft should be assessed
to determine students’ grasp of essay techniques.
assign the rough draft essay for homework, and spend the last
portion of class reviewing basic points of essay composition.