A farmer needs to take a dog, a goat and a bag of corn across a river. His boat can only carry him and one other thing. If he leaves the dog alone with the goat, the dog chases the goat. If he leaves the goat alone with the corn, the goat eats the corn. How can he get everything across safely?
Image source: File:Illuminated illustration of the wolf, goat and cabbage problem in the Ormesby Psalter.jpg (Wikimedia Commons)
In this post:
- What a plan is, and the What, When and Why of planning
- Goals, information and conditions
- Logic games that train your thinking
- The river crossing puzzle to solve, a planning template and a quiz
Plans help you reach goals
A goal is something you want to achieve, like raising $500 for a class trip or solving a puzzle. A plan is the set of steps that gets you there. Good plans answer three questions:
| Question | It asks… | Class trip example |
|---|---|---|
| What? | What needs to be done? What are the steps? | Hold a bake sale, collect the money, book the bus |
| When? | In what order? By what date? | Bake sale on Friday; book the bus by the end of the month |
| Why? | Why is each step needed? | The bake sale raises money; the bus must be booked early because they fill up |
Before you plan: information and conditions
- Information available: what do you already know? (In the puzzle: there is one boat, and three things to carry.)
- Conditions: the rules or limits you must stick to. (The boat holds the farmer and one thing; the dog can’t be left with the goat; the goat can’t be left with the corn.)
- Goal: what does “finished” look like? (Everything safely on the other bank.)
Logical thinking means using the information and conditions to work out which steps will and won’t work, rather than just guessing.
Activity: the river crossing
Try it: get everything across
Click the dog, the goat or the corn to put it in the boat (or leave the boat empty), then click Cross the river. Can you do it in 7 trips?
Logic games
Puzzles and games are a fun way to practise planning and logical thinking:
- River crossing puzzles, like the one above, with different characters and rules.
- Sudoku: fill a grid so every row, column and box contains each number exactly once.
- 2048: slide numbered tiles to join matching pairs and build up to the 2048 tile. You have to think a few moves ahead.
- Chess, draughts (checkers) and all-fours also reward planning ahead.
Watch: another river crossing riddle
This animated TED-Ed riddle has different characters and rules from the farmer’s puzzle, but the same kind of thinking. Pause the video when it tells you to, and try to solve it before the answer!
Video: Can you solve the river crossing riddle? – TED-Ed – https://www.youtube.com/watch?v=ADR7dUoVh_c
Plan it: a class event
In a group, choose a goal, such as a class bake sale, a sports day for younger students or a class clean-up. Copy and complete this planning template.
| Planning question | Your answer |
|---|---|
| Our goal | |
| Information we have (people, money, time, places) | |
| Conditions (rules and limits) | |
| What: the main steps | 1. 2. 3. 4. |
| When: the date or order for each step | |
| Why: the reason for each step | |
| How we will know we reached our goal |
Self-check quiz
Click the best answer. You get feedback straight away; only your first click counts towards your score.
1. A goal is…
2. Which planning question asks about the order of steps and deadlines?
3. In the river crossing puzzle, “the boat holds the farmer and one thing” is a…
4. In the farmer’s puzzle, what does he take across first?
5. Why is it useful to ask “Why?” for each step of a plan?
6. Which of these is a logic game?
Related posts on islandclass.org
For later, in Forms 4–5 (CSEC IT): these go deeper and are for when you reach CSEC Information Technology.
Next: Thinking Like a Computer Scientist
Syllabus link: Forms 1–3 ICT curriculum, Module 5, Objective 5.3 – apply logical thinking skills to find solutions to problems.
Attributions to media used in this post:
- Illuminated illustration of the wolf, goat and cabbage problem in the Ormesby Psalter.jpg – Unknown illuminator (Ormesby Psalter, Bodleian Library MS Douce 366) – Public domain (via Wikimedia Commons)
- Video: Can you solve the river crossing riddle? – TED-Ed (YouTube)
Updates
2026/10/21
– Fixed the activity code so its buttons keep working.
© 2026 Vedesh Kungebeharry. All rights reserved.