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Illustration of junior detective party

Junior detective party

BirthdayKids 7-12Budget costMedium effortIndoorAny gender

Young detectives dust for fingerprints, decode messages and interview suspects to solve the case of the missing cake.

Guests
6-14 children
Party length
2 hours
Prep time
Half a day
Ages
7-12

What it could look like

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AI-generated example of a junior detective party
An example of how a junior detective party could look on the day. This image was generated by AI.

What it is

A mystery party for kids. The birthday cake has been “stolen” and the guests must find out who did it. They learn detective skills, then use them to follow clues around the house.

Plan ahead

  • One week before: write the story. Choose 4 “suspects” (family members or toys) with an alibi each, and decide who did it.
  • Two days before: make 6-8 clues: a footprint, a hair, a torn piece of fabric, a coded message, a fingerprint.
  • The day before: hide the clues and the cake.

Activities

Fingerprinting

Rub a soft pencil on paper, press a finger on it, then lift the print with clear tape. Compare with the prints on the “evidence”.

Secret codes

Teach a simple shift code (A=B, B=C…). Detectives decode the ransom note.

Invisible ink

Write with lemon juice or a UV pen and reveal it with a torch.

Clue hunt

Each clue rules out a suspect. Give teams a “suspect board” to tick off.

Food and drink

  • “Evidence bags” of popcorn
  • Magnifying glass biscuits (round biscuits with a jelly sweet window)
  • Sandwiches labelled “Case 001”
  • The rescued cake

Tips

  • Make sure the culprit is a grown-up or the dog, not a guest.
  • Pair younger children with older ones for reading clues.

On the day

  1. Detective academy (15 min): ID badges, magnifying glasses and notebooks.
  2. The crime (5 min): the birthday cake has gone missing - only a ransom note is left.
  3. Detective training (25 min): fingerprinting, secret codes and invisible ink.
  4. Clue hunt (25 min): find clues around the house and rule out suspects.
  5. Food (20 min).
  6. The accusation (10 min): detectives name the culprit and find the cake.

Shopping list

kids detective kit
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fingerprint kit kids
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invisible ink pens
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magnifying glass kids
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detective party decorations
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spy notebook
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