Detective Fingerprinting Kids Activity

I got a little creative with my activity for our church’s 8-11 year old girls this week. I originally just thought it would be fun to fill out a worksheet to analyze their fingerprints. Well, one thing lead to another, and I came up with a full blown detective fingerprinting kids activity, complete with a cookie thief, a creepy recording (thanks to my husband for providing his voice for me to play around with), and secret messages. It was SO fun!!! Took me a whole day to make it, but it was totally worth it. Way more exciting than a worksheet, and I still got them to fill it out as part of the activity. This would also make a great girl scout or cub scout activity!

This activity is going to take a little bit of prep work, but I’ve done my best to outline everything you need and how to put it all together. Let me know if you have any questions.

Supplies Needed for this Detective Fingerprinting Kids Activity:

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• free printables
• detective recording on YouTube
• large manila envelope (about 11.5×15 inches)
• 3 6×9 inch envelopes
• packing tape
• a small scrap of paper for each child
• a pencil for each child
• clear tape
• bleach
• q-tip
• black light
• at least 3 sheets of printer paper
• a fingerprint worksheet for each child like the one here. Label the two spots where their thumbs should go.
• magnifying glass (optional – might be fun to get one for each child)
• a small notebook for each child
• cookies!

Activity Preparation

Step 1: Choose a child ahead of time and ask them if they are willing to be your criminal. Probably best to choose an outgoing child for this who won’t get their feelings hurt by being labeled “the criminal”. Take their thumbprint (using the method at the end of this post) and put it on a blank piece of paper. Make sure it’s their THUMB! Write the words “Suspect’s Thumbprint” on the paper.

Step 2: Have the child bring you the shoe they plan on wearing to the activity. Rub the sole of the shoe around in some dirt and press it on a blank piece of paper to make a shoe print. Put packing tape over the entire shoe print to make sure the dirt stays in place. Write the words “Suspect’s Footprint” on the paper.

Step 3: CAREFULLY pour a small amount of bleach into a small cup or container. Make sure to follow all of the precautions on the bottle of bleach. Use gloves, and do not get it on your skin or in your eyes. Protect your surface and clothing and do this part outside or in a well ventilated area. Think of another clue about your suspect and write the message by dipping a q-tip in the bleach and using that as your writing utensil. Allow the bleach to dry completely on the paper. The writing will show up only when exposed to a black light later.

Step 4: Instruct the child to act like they don’t know what’s going on at the activity, just like everyone else. Tell them to make sure to wear the shoes they made a print of (and any other clothing item in your other clue) and tell them where you will be hiding the cookies. Tell them that the other children will be interrogating them at the end of the game, and they should say things like “I’ll never tell!” Then finally they should give in and give the other children a hint as to where the cookies are located.

Step 5: Use packing tape to tape “clue #1” printable to outside of a small envelope and fill with fingerprint worksheets, sample worksheet (filled out with your own finger prints), scrap pieces of paper, and the suspect’s thumbprint paper.

Step 6: Tape “clue #2” printable to outside of a second small envelope and put the suspect’s shoe print paper inside.

Step 7: Tape “clue #3” printable on the outside of the third small envelope and put the secret message inside. Make sure it’s dry first!!

Step 8: Tape “top secret” and “detective agency” printables on the outside of your large envelope using packing tape. Put pencils, notebooks, magnifying glass(es), clear tape, “mobile device” printable, and three filled clue envelopes inside.

Step 9: Hide the cookies at the beginning of the activity. I just got some store-bought cookies and wrote “Valuable Cookies” on the outside of the package. They thought that was funny. Also, put the black light somewhere in the room.

Detective Fingerprinting Kids Activity

Step 1: Pretend like you aren’t sure what you’re doing for the activity today. Once all the children have arrived, have someone doorbell ditch the top secret package on the doorstep. This isn’t 100% necessary, but I can tell you that the girls LOVED it. They were all trying to figure out how the package got there.

Step 2: Have the children open the envelope and read the piece of paper that says a message has been transmitted to your mobile device. Act all surprised and start playing it. You can find that recording on YouTube here. You will need to pause and resume playing it several times.

Step 3: Work your way through each of the the clue envelopes and have the children record all of their findings in their detective notebook. They will do the fingerprint worksheets and compare their prints to the suspect’s (instructions below), compare their shoe prints to the suspect’s, and read the secret message using the black light.

Fingerprinting Instructions

1. Rub the side of a pencil on your scrap piece of paper to create an “ink pad.”

2. Rub your finger on the paper. Make sure to cover the entire area on your finger.

3. Take a piece of clear tape and place it on your finger. (I went around with pieces of tape so the girls didn’t make them too big.)

4. Carefully peel off the tape, which will have an image of the fingerprint on it, and place it on the correct spot on the worksheet.

5. Have the children fill out the entire worksheet, labeling each of their type of fingerprints. I found it helpful to label the worksheet ahead of time with the word “THUMB” so they could tell which prints were the ones they needed to compare with the suspect’s. Tell them to look at the suspect’s thumb print and compare with everyone else’s. Is it a whorl? arch? loop? Who else has that on the thumb print spot on their paper? Other thinking questions to ask: What’s the most common type of fingerprint? What’s the least common? Does anyone have a unique fingerprint, like a double loop?

Solving the Crime

When the children have finished all of the clues, tell them to finally work together to figure out who the criminal is. Once they have their suspect, sit him/her in a chair and tell the other children to interrogate her. After a little bit of time, tell the suspect you will release them if they give a clue that leads to the cookies. The criminal gives her clue, the kids find the cookies, and you celebrate that “The Case of the Missing Cookies” has been solved! Hooray!

I hope your kids love this detective fingerprinting kids activity as much as my girls did! Click here for fun kid craft ideas and go here for more fun primary activity ideas for kids.