This document describes a Jenga game that is used to demonstrate test-driven development principles. It outlines 3 rounds of play where one player is the developer building the Jenga structure and the other is the tester rolling dice to "find defects" and require the developer to remove matching blocks. The goal is to build the structure iteratively in rounds of 9 blocks while incorporating testing throughout development.

1. Agile Jenga
Or Why TDD Matters

2. Agile Jenga :: Let’s Get Started
• Separate into pairs
• Each pair takes a pair of dice (one red, one white),
and a set of Jenga blocks; these are numbered.
• Decide who will be the developer and who will be the
tester
• You will need a small sheet
of paper and a pen

3. Agile Jenga :: Building
Requirements
The Developer will build a structure; it must meet the
following requirements:
• Use ALL Blocks
• It must be at least 3 “stories” tall (a story consists of
at least one horizontal piece and one vertical piece)
We will build this structure
in 3 rounds, with each
person being the tester at
least once

4. Agile Jenga :: Round 1
Developer
• Build the structure
Tester
• At the End, Run Your Tests: Roll the dice 4 times (match
the red and black numbers rolled to the blocks)
• Blocks that match the rolls
must be removed by the
Developer and the tower
must be rebuilt if necessary

5. Agile Jenga :: Round 2
Developer
• Build 9 blocks of the structure
Tester
• At the end of each 9 Block iteration, Run Your Tests: Roll
the dice 4 times pulling matches in the structure as
defects to be removed. Ignore blocks not in the structure
or previously pulled.
• Blocks that match the rolls must
be removed by the developer
and the tower must be rebuilt if
necessary
Move onto the next iteration of 9
blocks to be built (4 iterations)

6. Agile Jenga :: Round 3
Tester
• At the Start, Run Your Tests: Roll the dice 4 times and record the
numbers (reroll if any have been previously rolled, so that you
have 4 sets of numbers); keep these “private” (Easy Variant: roll
the dice at the start of EACH iteration noting the 4 numbers)
Developer
• Select and build 9 blocks of the structure
Tester
• As the structure is built, remove
any matching numbered blocks
as you see them
Move onto the next iteration of 9
blocks to be built (4 iterations)

7. Agile Jenga
- Debrief -