K–2ComputationPlanned
Following and giving precise instructions
Algorithms as step-by-step instructions: following directions on a grid, giving instructions to a friend or a floor robot, and finding and fixing mistakes ('bugs') in a sequence of steps.
math.comp.following-instructions
The lesson for this topic has not been written yet. The outline below is part of the curriculum map and has not been reviewed.
Builds on
No prerequisites — start here!
You will learn to
- Follow a sequence of movement instructions on a grid and predict where it ends.
- Write a sequence of instructions to reach a target, and test it.
- Find and fix a mistake in a sequence of instructions.
Definition
- An algorithm is a precise list of steps that can be followed to complete a task.
- A bug is a mistake in an algorithm that makes it do something unintended.
Theorem
- Changing the order of the steps can change the result.
- Instructions must be precise enough to be followed without guessing.
Common misconceptions
- Thinking a robot or computer 'knows what you mean' when instructions are vague.
- Believing there is only one correct algorithm for a task.
Leads to
Optional discoveries
- One thing after another A list of instructions is a chain of actions carried out one after another.
Further reading
- Tim Bell, Ian H. Witten and Mike Fellows, Computer Science Unplugged