forensic style investigation activities

Discussion in 'Science Technicians - General Discussion' started by Heidi Ross, Nov 7, 2019.

  1. Hello all does anyone have any good ideas for yr 7/8 forensic style investigations? I would be grateful if you are able to share them please? I have just been notified that at end of November we are having a yr 7/8 taster day and will have 22 students in science each hour for the whole day. I have a few ideas but was thinking of maybe having 3-4 ideas that they can move around as a circus of activities. they will only have one hour to complete any activity.Thanks.
  2. karen b

    karen b COMMITTEE

    chromatography of inks (who wrote the ransom note)
    shoe prints in plasticine or make a plaster cast
    fibre identification using a microscope
    flame testing soil samples doctored with various salts.
    blood splatter - what height was the blood at the scene dropped from. Takes a bit of prep
    Heidi Ross likes this.
  3. have you done the blood splatter one? how do you/they do this please?
  4. Make fake blood
    Blood recipe:
    In 500 ml water
    1,000g sugar
    37.5 g cocoa or drinking choc powder
    7ml red food colouring

    Then use teat pipette to drop blood on A3 white paper from various heights measure diameter of spot. Graph the results

    Also DNA extraction
  5. I've used science spot over the years
    Heidi Ross likes this.
  6. karen b

    karen b COMMITTEE

    We set up stations with pipettes fastened to a metre ruler/clamp stand. They practiced on scrap paper then then had cm squared marked pieces of card to drop some blood on. They measured the diameter of each spot and drew a graph. There is a crime scene blood drop for them to measure and then use their graph to say the height it fell from.

    This is with year 7 girls. the boys school down the road did something similar, but not so tightly controlled, and they got very creative with whether the blood fell at an angle. I think it looked like a blood bath after they'd finished
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  7. Can't remember who originally suggested testing for blood group but we've used it a couple of times and think it's pretty cool.

    Use full fat milk with red and black food colouring for the blood, vinegar or lemon juice for a positive result (we use citric acid as it doesn't smell or have a colour) and water for a negative result. Make sure you use good quality milk, we found it worked better with Waitrose milk.

    We do it as part of a cluedo type day. I made laminated sheets for each character with A, B and RHESUS circles on, each sheet has a dropper bottle of A, B and RHESUS "reagents", contents of each bottle depends on required result. Positive clumps pretty well.
    Heidi Ross likes this.