Teacher: Stephanie Bagenstose
Grade Level/Subject Area: Grade 8/ Science.
Standard: 8.P.1 Understand the properties of matter and changes that occur when matter
interacts in an open and closed container. 8.P.1.1 Classify matter as elements, compounds, or
mixtures based on how the atoms are packed together in arrangements. 8.P.1.2 Explain…
Learning Objective: Students will conduct investigations and utilize technology and
information systems to build an understanding of chemistry. Students will demonstrate an
understanding of three mystery materials using physical properties such as density, chemical
reactivity, boiling points, and solubility..
Required Materials: Each student will have: goggles, apron, gloves (if required), 1 balance, 1
beaker filled with water, 3 unknown solid substances (wood, iron, copper, etc.) each material
labelled exhibit A, B, and C, 1 magnet, calculator, pencil, paper, density chart worksheet,
http://www.youtube.com/watch?v=QCfut6WcgQw (video explaining how to test unknown
chemicals), http://www.engineeringtoolbox.com/young-modulus-d_773.html (intro to densities
of matter) .
Anticipatory Set: Students will begin class by literally entering into a crime scene. The
classroom will be decorated with caution tape, as well as an outline of a body on the floor
by the door. There will be a police light going off, and a guest speaker on forensic science
(preferably a professor from UNCW’s criminology department) will greet them as they
take their seats. Students will be told that they are going to explore the world of forensic
science by collecting three unknown solid materials and conducting specific tests on those
items to determine the physical properties and come up with an educated guess on what
those materials are. They will be using their knowledge from the intro to densities website
as well as the you tube video to show they understand how to properly handle unknown
substances and can classify matter based on the atomic arrangements.
Instruction: The question asked at the start of the experimentation will be “how can
knowing the physical properties of a substance help to identify it?” Time required for this
lesson will be 45-55 minutes. Students will be asked to take notes on the young’s modulus
website we will be using to fill in the blanks on their density chart worksheets. After this
sheet is filled in, students will watch the “you tube” video on how to collect materials
properly, and once completed, they will each gather materials for their groups before the
experiment stage can begin. Teacher will be double checking that each group has the entire
checklist of materials. Once it is determined they have everything needed, they can begin
collecting the substances. There will be three large beakers in the front of the room labelled
“Exhibit A, Exhibit B, and Exhibit C”. Students will be required to treat those materials
like an actual crime scene evidence and will discuss how to properly handle each material
before bringing it to their table. Since they do not know what each material is, they will
have to handle carefully, label properly, and use proper precautions demonstrating they
understood the video. Each group will begin by recording on a sheet of paper the visual
characteristics of each substance. They will then be asked to record the physical
characteristics such as magnetism and malleability. Teacher will ask questions like, “does it
bend?” “Is this material magnetic?” etc. The next step will be having the students calculate
density of each material using the formula they learned from the website (D=
Mass/Volume). For the volume portion they will use the beaker full of water to determine
water displacement. This is the final point. After this, students will be asked to make their
educated guess on what each material is using the resources they were provided earlier.
Teacher will then discuss how each characteristic is unique to the substances and helps
determine their identity. .
Independent Practice/Assessment: The students will demonstrate a full knowledge of
what they have just learned by creating a “Police log book detailing all the evidence of the
scene, locations of each sample found, how each sample could possibly have led to the
victim’s death, etc. This will show the ability to use technology systems and resources
available to develop an understanding of chemistry. Once completed, the true identity of
each substance will be revealed and the group with the most correct answers will get extra
credit on their tests at the end of week.
Closure: The guest speaker will conduct a question and answer seminar with the students
to educate them on the field of forensic science and demonstrate how it relates to matter,
density, etc. Students will be asked to go home and conduct their own “crime scene
investigations,” using popplet or powerpoint and bring what they have discovered to the
next class for a group discussion.