Last week in First Grade Reading, we performed another series of Crime Lab tests designed to get us closer to discovering the culprit in our Pilfered Hippopotamus Mystery.
The first station required testing the white powder found on Danny. At the station there was a cup of mystery white powder. Was it powder used to make cookies, or powder used to make pie? The kids used an eyedropper to add Iodine to the powder. The station directions informed them that if the powder turned bright yellow, it was cookie powder. If the powder turned purple or black, it was pie powder. Who looked guilty based on the result of the test — who brought cookies and who brought pie?
Next, the students tested the melted ice cubes to determine if they contained a mystery substance. The station directions informed them that if they dipped pH paper in the melted ice cubes and the paper stayed yellow, the ice cubes were simply water. If the pH paper turned green, the ice cubes contained a mystery substance.
At the next station, we examined three cups. One contained salt crystals, one contained sugar crystals, and one contained the “mystery crystals” found on Danny at the scene of the crime.
The kids looked closely at all of the crystals and tried to determine if the mystery crystals best matched the salt crystals (which were chunky) or the sugar crystals (which were smooth and shiny).
At the Footprints station, the kids examined the footprints left at the scene and compared them to the footprints of the five club members to determine who had made the tracks found at the scene.
Finally, we performed a tape lift to determine what particles were stuck to Danny. We ripped off a small piece of tape and pressed it to Danny.
We then stuck the piece of tape to a white piece of paper to examine what we had removed. Was it dog hair? Grass? And who looked guilty based on what we found?
We then sat down to take a long look at our Data Sheets and Clue Boards. Who looked guilty based on the tests we had performed? What did we think happened based on the evidence we had found?
I sent the Data Sheets and Clue Boards home so that the kids could use them to complete their homework assignment — writing a paragraph or two that explains their theory of what happened and their best guess as to who took Danny.
Throughout this unit, I have been impressed by the kids’ attention to detail and their ability to make appropriate inferences. There are a lot of pieces to tie together here, and they have shown great facility at taking information obtained in one way and applying it somewhere else. Most of them have been careful not to jump to conclusions, and to modify their theories when the evidence contradicts them. If I needed a group of detectives, I would hire them for sure! If I needed a group of first graders who could pay attention to a text, make inferences about it, and connect it to other texts and situations, well, I’d hire them for that, too!