SAFETY IN THE CLASSROOM
Carol Lutsinger
Safety in the classroom laboratory is as important as it is in an actual laboratory.
Careless habits developed in elementary school may cause problems in the
middle school and high school lab setting. In order to help students understand
the need to develop careful correct habits, I developed this lesson plan.
The TEKS include lab safety, and this is an easy-to-put-together activity.
Classroom prep: less than one hour, depending on how organized you are and
how elaborate you want this project to become.
Lesson: appropriate for all elementary students.
Supplies: water, graduated beakers, droppers, vinegar, water, safety goggles,
clean up supplies (paper towels), calculators might be fun to use to find averages
Upon entering the classroom area, the students should see large Caution signs
indicating danger nearby. By this I mean a hallway or outside wall. When the
students enter and seat themselves, begin to ask questions about things they
have noticed on the way to class.
Discuss some general safety rules. Tell the children that in an actual lab
there is a source to shower in case of spills of hazardous chemicals. Indicate
an area of the classroom that will be the emergency shower. You may want to
use a bucket arrangement, but pretend to have a shower with a pull handle.
Ask the children how many of them know someone who does not take all the Rx
prescribed by a doctor. In my area of the country, access to medicines from
Mexico, families trading prescriptions, sharing prescriptions, etc. led me
to prepare this activity.Do they know someone who takes medicine meant for
someone else? Explain the dangers in this.
Tell them they have been invited to test a new product that might contain carbon
dioxide. Explain how doctors prescribe medicine by body weight and we need
to find out how many drops there are in 10 ml. Then test and find the average.
Explain that scientists test products numerous times before any product is
allowed to be sold in the marketplace. Explain about the importance of never
changing the data found. Tell them the product is possibly dangerous and that
you will be looking for lab safety activity. If any liquid spills, the lab
partner rushes them over to the “shower” and cleans them up while
another partner calls emergency help.
I buy the brown glass bottles with small droppers from a local pharmacy for
authenticity. Half-fill bottles with vinegar or water. Each team will need
one of each. Tell students the lab has mixed up its chemicals and they have
to find out two things, which bottle contains the acid, and which contains
the water. Explain the wafting technique if you have not already done so.
Assign task of materials manager to get safety goggles, two bottles of chemicals,
and a graduated beaker that will measure ten ml, and return to the group. Use
science log books to draw an appropriate table to record data. They will carefully
test for the chemical, then proceed to measure 10 ml drop by drop, counting
and recording with tally marks until they reach the correct amount.
Repeat the test 5 times, then find the average number of drops in 10 ml. Discuss
any differences of totals with the class as part of the lesson about repeated
testing, variables, etc.
When the first spill occurs, dramatically get that person to the "shower" and
call "HAZMAT" to clean up hazardous waste. My facilitator and assistant
principal were in my classroom one day when this was going on and they thought
I was really having a crisis!
Do lots of talking with the class about the importance of repeated testing,
controlling variables, and listen to what the students have to say about taking
medicines. You may be very surprised.
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