GEMS Science Class Summary 3/25/13

Analyzing the Evidence

This week began the testing phase of our investigation. The students worked in teams analyzing evidence found at the scene.

After reviewing the clues we have so far the students rotated through five stations where they conducted tests to give us a clearer picture of what could have happened to our victim, Felix.

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Fingerprints on cups found at the scene were compared to the fingerprints of our suspects. The gas from a few drops of Krazy Glue, which was added to the evidence bag containing the cups, made the fingerprints turn white so they could be more easily seen. One scent from each of our 5 people of interest were compared to a shredded towel found at the scene, which had a lingering scent. Students had to see which scent most closely resembled the one on the towel.

The cola found in the two cups at the scene were compared to regular cola using pH strips. Did the two cups of cola closely resemble the pH of the regular cola or was something added to one of them? Cotton and wool threads were compared to the threads found at the scene by watching how each type burned. Did it burn slowly or quickly?  What did the ashes look like?  Finally, a mysterious brown stain was compared to a brown felt marker found in one of the suspect’s pockets and the coating of a brown kind of candy one of our suspects enjoys eating. Which one did it turn out to be?

Next week we will share our findings, performing tests together to settle any disagreements over results. The crime is slowly beginning to take shape, but much confusion still exists as we try to narrow down which clues lead us to the murderer and which ones take us in the wrong direction.