Playing a money counting game
Source for the earn-and-pay format in the classroom money-counting activity.
Open primary source ↗Evidence & method
Sources and testing
This page lists the public sources used for the site's money activities and accessibility notes. It also records the search-volume check and the method used to test each puzzle.
Explore planning
Source for the idea that games can exercise attention, memory, creative thinking, and choices.
Open primary source ↗Sorting logic blocks
Source for the rule-inference and explain-why approach used in the logic puzzles.
Open primary source ↗Understanding Success Criterion 1.4.3: Contrast (Minimum)
Source for the normal-text contrast target of at least 4.5:1 used on the site.
Open primary source ↗Media Queries Level 3
Source for the screen and print media types used in the print stylesheet.
Open primary source ↗Search measurement
What people look for
Recorded 25 October 2026 for United States. Eight queries checked. Published cost: $0.09.
| Query | Monthly searches |
|---|---|
| printable logic puzzles | 3,600 |
| jigsaw puzzle benefits | 320 |
| family money games | 20 |
Mechanical quality check
How each answer key is tested
- 1
Encode each puzzle as four categories with four values per category.
- 2
Generate every possible assignment of values to rows.
- 3
Apply every clue as a true-or-false filter.
- 4
Count the assignments that pass all clues.
- 5
Keep the puzzle only if exactly one assignment passes. The answer key is that assignment.
Current set: 3 puzzles · 13,824 assignments per puzzle · 1 accepted solution each.