Crime Scene Tampering

This lesson will test my rookie crime scene investigators skills of observation and thoroughness of their written documentation.
On day 1, investigators will go to the crime scene (science lab). There they will find a huge mess which has been left behind (chairs turned over, trash left, spatter on the walls, fingerprints, etc.). Teams will make their initial visual observations. From there, two investigative teams at a time will process the scene taking photographs, documenting their observations, taking measurements, etc. No evidence will be collected! As each team completes their processing, they will return to "headquarters", download and print their crime scene photographs. They will observe and discuss their photographs and documentation to get an accurate analysis of their crime scene.
On day 2, investigative teams will return to the crime scene for a "second look" to verify their documentation. What they don't know is that I have "tampered" with some of the evidence, such as repositioned a chair, smeared a fingerprint, left an extra soda pop can, etc. Before each team returns to the briefing room with the other teams, I will questioned them as to their findings to see if they picked up on the tainted evidence. This will be the first assessment tool for this lesson. I will instruct the team as they return to the briefing room to document their findings for future reporting and to not discuss anything with other investigative teams.
When all teams have completed their "second look", I will inform them of the objectives of the lesson and what they will be evaluated on. As stated before, the first assessment tool was to see if they discovered tainted evidence. The second part was if they photographed and documented the tainted evidence. The third part will be if they discovered all the tainted evidence. The fourth part will be the written report documenting the tainted evidence from day 1 to day 2. The fifth part will be the verbal briefing to the other investigative teams.