What Do Forensic Scientists Do?

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Students will explore like detectives ( forensic scientists) by using fingerprinting techniques in the classroom.

Big Idea

Detectives (forensic scientists) help communities solve crimes by asking questions, using fingerprinting and other scientific clues that identify people.


7 minutes


As my students are in learning position on the carpet, I ask them to "What do you know about detectives?    

Using what they know, my scientists began to express their understanding of what a detective does in the world of science.  In this case, I give them a clue.  I say, "Think about the detective television shows." Once I mention Scooby Doo, Dick Tracy, and Roger Rabbit, my students have many statements to make about detectives by virtue of their exposure to these programs. They do not know the formal title of forensics scientists but they can express ideas about finger prints and crime scenes.  




10 minutes


As the students are gathered on the carpet, I introduce them to Bill Nye the Science Guy.  I say, "Bill Nye is a super scientists who teaches students about many different scientists and their practices. Today Bill Nye is introducing us to a type of scientists, the detective. Let's pay close attention because we are going to do the work of a detective today."

We begin by viewing a Bill Nye video  (beginning at 1:00 and ending at 5:59) about fingerprints and forensic scientists.   This video was selected for it's quality however, he discusses other aspects of forensic science while this lesson focus is just on the forensic field scientists who collects evidence like fingerprints.


After the video, I asks questions about what we have seen.  For example, "What did the detective do get the fingerprints off the clear case."  The students share their answers with their shoulder partner.




20 minutes


I say, "Today boys and girls, you have seen a type of scientists in action.  You watched a detective, find fingerprints.  You are going to become detectives and identify your own fingerprints."  


The students will work in predetermined partnerships.  This selection process is necessary to ensure that a peaceful learning environment exists for this specific lesson.  Each partnership will share a water-based black marker.  I say, "This is the only time I am giving you permission to write on yourself with a marker."  Scientists work together and sharing helps promote scientific discourse. Each student will have his/her own fingerprint card and a post-it for graphing their fingerprints as well.  


Before the students transition to their tables, I model how to take a fingerprint.  I say, "You have five fingers on each hand and each finger has a name."   I identify each finger starting with the thumb, the pointer, the index, the ring finger, and the pinky.  I make a gesture with each finger as I name them.  Next I say, "You have a fingerprint card with a place for each fingerprint to be placed on the card only once."


Students will use water-based black markers.  Starting with the left thumb, the student rubs the marker over the tip of the finger from the line to the tip of the finger nail. Students holds their finger on the card as they count to 10.  


  • Roll the student's thumb pad (from the top knuckle to the tip) on the ink pad. Make sure the black marker covers the entire pad of the thumb.


  •  The partner helps the student rub the marker over the tip of his/her thumb.


  • Roll the students inky thumb pad from right to left in the square you have labeled "Thumb." Make sure to do this slowly and carefully, and to do it only once. I say "Rolling your finger back and forth will smudge the print."  Ensure that full contact has been made by visually inspecting the print.


  • Repeat the process for each remaining finger on the students left hand, making sure to match the prints with their correspondingly labeled boxes. Label the chart with which hand was fingerprinted after you have finished taking prints.


  • Students should let their fingerprints dry before moving the card.  The students are only fingerprinting the left hand. 


A management tip is to provide everyone with a Wet-One or paper towel and suggests that they were a dark shirt to school the day before the investigation.








15 minutes


This science lesson is very fascinating to my kindergarteners however to add more rigor to it, I suggest we classify our finger prints on a graph.  I say, "There are three main fingerprint types. They are the arch, whorl, and loop."   The graph is labeled as such.  When students were developing their fingerprints in partnership, I instructed them to use a post-it to put their name on the back and their left thumb print on the front.  


Once we complete this segment of the lesson, I ask the students to view their fingerprints on the post-it and decide if they have an arch, whorl or loop.  Each student then re-verifies their fingerprint type with a shoulder partner.  I get their attention by saying, "1,2,3 all eyes on me." 


The students are sitting on the carpet in a line and I call them up one at a time.  I have the three types of fingerprints enlarged and placed on a graph.  The graph was created in a word document and is displayed on the ENO Board.  The students place their post-it in the appropriate place on the graph.  This is a quiet a process because the students already discussed their fingerprint types. The process continues down the line of seated students.  Upon completion, we tally the types of fingerprints and I share our findings. I say, "Scientists share their findings with the people they work with."




5 minutes


The lesson ends with me reiterating the skills of a detective and I say, "There is a scientists that takes fingerprints, they are called forensic scientists."  I asked the students to use a "bear voice to say forensic scientists, as we all as a baby voice, a a whisper voice.


As usual, I encourage them to consider this field of science as a possible career choice.