Crime Busters

Crime Busters

Description: To determine who committed a crime, students will analyze clues that may include testing of unknown powders, paper chromatography to identify ink, matching fingerprints, shoeprints or tire tracks. 


Event Supervisor: Shane Storks


 event supervisor info
 Download the current rules here.  newr 2
 From the  Event Coach Workshop.
 Sample answer sheet
 Practice Investigation Kit Insert
 This event uses an optical answer sheet (e.g.,Scantron) Learn more
more event info be careful
  There may be a "Quick Start Kit"  available for this event. 
 See the Elementary Workshop List for this season
 Report problems at This email address is being protected from spambots. You need JavaScript enabled to view it.




 elem faq button web



Will a team be marked lower if they identify 2 suspects as guilty if the correct answer is one of them, even if the evidence is correctly evaluated?

Points are awarded for identifying the correct suspect(s). If innocent suspects are also named, a fraction of those points are taken off.

Are there any restrictions regarding the style, size, or power of the magnifying glass?

The magnifying glass must be one piece, and work without being plugged into an outlet.

How will the Chromatogram portion be scored?

A high-scoring chromatogram will have six neat designs that implicate the correct suspect(s) and travel straight up the paper running into each other.

If a student already wears glasses, do they still need to wear safety goggles?

Yes, splash-proof goggles which can fit over prescription glasses are required. There should not be any gap between the goggles and the student's face. Goggles which look like glasses are not adequate.

Will the fingerprints be identified as from a right or left hand, or by the finger names?

The fingerprints may not be labeled. Students should learn how to identify them.

Will students use rubbing alcohol to test the powders?

No. Rubbing alcohol is used only for chromatography.

Will students be asked to identify the types of finger prints, e.g., arch, loop, whorl?

No. However, it may be beneficial to mention this vocabulary when learning about fingerprints to make it easier to describe them.

How will students transfer powders to the paper? Will they have to pour it?

Students will be provided one plastic spoon for each cup.

Will fingerprints be presented as actual size?

Yes.  They will not be scaled.

Will the number of each part on the test match up with the numbers on the Scantron?

Yes.  All the Scantron questions will be implications of Suspects A-E.

1 will be for the powders portion, 2 will be for the chromatography, 3-5 will be for the finger, foot, and tire prints respectively, 6 will be for unspecified evidence, and 7 will be for final criminal implication.

How are points distributed in Part 2 of the test?

Half of the points come from performing the chromatography experiment correctly, and the other half comes from implicating the correct suspect(s).

How much time will students have to take the test?

All students will be given the same amount of time.  Our intent is to provide 25 minutes.

May the students bring anything to help secure the chromatography paper at the proper height above the rubbing alcohol (tape, binder clip, etc.)?

No. The students will be provided everything they need. To see how this will look in the testing room, view the chromatography video we've posted.

How many plastic cups are the students given for testing liquids in the powders?

There are at least 18 cups at each station, but there will likely be many more.  The students will have more than enough and may ask for more if needed.

If hair samples are used, would they be real hair or a photograph?

The students could be presented with either.  If they are physical samples, they will be presented as a microscope slide.  If they are photographs, they will be very magnified.

At the competition, how many grams of powder will be in a cup? How much water will teams be provided?

Cups will be filled with about 15 grams of powder total.  Teams will be given about 10 mL of water.  Students should learn to only use drops of water when experimenting.

Might "unspecified evidence" include the subject of blood?

The test will be age appropriate.

For example, blood found at the crime scene could be from the criminal accidentally getting a paper cut while committing the crime. No blood spatter analysis or other information relating to violent crime will be included.  Students could be required to match characteristics of blood, such as blood types and DNA. 

Will students be scored for naming all of the powders contained in each of the suspect containers? Or is the powder identification practice sheet just for their own use to aid in suspect identification?

Students will be scored on their ability to name all powders in all six cups.  There is a handwritten portion of the test for this, separate from the Scantron portion.

Are the liquids added to the powders on the black paper? Or are spot trays available?

Liquids should be added to the powders in the plastic cups.  Students will be provided spoons and extra empty cups to split up their samples and conduct tests on them.   The black paper is helpful for looking at dry powders up close.

Will the students be expected to write an essay to support their answer?

No.  The only written part is the identification of powders.

A portion of the Crime Buster answer sheet will be "Scantron"-like

This is a change from how students recorded answers on last year's test.  It is not a Scantron form, but is extremely similar.

See an example of this new format.

Can photographs be included on the notes page that each team may bring?

Yes, any information may be included, provided that it is printed or written directly on the page.

How will the Scantron form be used for recording the powders in each cup? Also, how will it apply to the other categories of evidence?

Powder identification is still written and hand scored as before.  Every "implication question utilizes the Scantron, and will be labled to match the form.  Students will be given a numbered list of very specific implication questions to avoid confusion.  For example, students might be asked which suspect(s) has the same powder(s) on them that were found at the crime scene.  Similarly, they could be asked which suspect's ink sample on the chromatogram matches the ink sample from the crime scene.

If more than one suspect matches a particular piece of evidence, how will students be able to answer multiple suspects on a Scantron form? Will the answers have predetermined specific combinations?

In our traditional Scantron, students could only pick one answer among A thru E, and multiple correct answers would require the answers to include the specific combination as one potential choice.


An important aspect of this new "Scantron" format is the ability to score multiple correct answers in the same question.  For example, if both B and D are correct matches, the student would be expected to mark both.  Because of this new scoring capability, any combination could be answered.  Students will be expected to select only the correct matches, and may lose points for answering incorrectly.



Can you provide more information to help us interpret the practice tournament scores? For instance, what is Part A, and how many points were possible?

The scoring sheet lists parts A - G, and the rules lists parts 1 - 7.  Those directly correlate.  We changed the rules and the test this year to reduce confusion for the students, but the scoring program hasn't caught up yet.  


Compare your score to the possible points: 

Part A = Part 1: 38 points

Part B = Part 2: 18 points

Part C = Part 3: 6 points

Part D = Part 4: 3 points

Part E = Part 5: 5 points

Part F = Part 6: 15 points

Part G = Part 7: 15 points

Should we expect multiple criminals to have the same matches in every section of the test?

They might or might not have the same matches.  Students should only implicate two criminals if they see two suspects with the same number of implications over all sections.


Is chalk the same as calcium carbonate?

Yes, however the calcium carbonate provided on the test will be in powder form and uncolored. Keep in mind that chalk may contain extra ingredients besides calcium carbonate.

Is Tums the same as calcium carbonate?

Tums contains calcium carbonate as the active ingredient, however it will likely contain extra ingredients that can interfere with reactions.

Where can I purchase calcium carbonate?

Powdered calcium carbonate is available in bulk from several sources on Amazon at a cheap price.  You may also find it at some pharmacy stores in powder form, or you may have to buy it in tablet form and crush it. Chalk can be a viable substitute if it is pure calcium carbonate.