Why a checklist before every lab
A lab bench is a place where a careless step can spill water, drop a tool, or ruin a careful measurement — and where good habits are built for every science course that comes later. A pre-lab checklist is not bureaucracy — it is the routine that makes safe, prepared work automatic, so that on the day something goes sideways the student's hands already know what to do.
It also does something quieter: it forces the student to arrive ready. The most dangerous lab partner is the one who skimmed the procedure in the hallway. This checklist closes that gap. Print one for every experiment, work top to bottom, and do not pick up a single tool until the last box is checked.
The goal is not to follow rules. It is to walk to the bench already knowing the hazards, the steps, and the result you expect.
1 — Safety
Nothing below this section happens until everything in it is done. No exceptions, every lab, every time.
- Splash-proof safety goggles on — over the eyes, not pushed up on the forehead.
- Safety gloves on if the day calls for them; sleeves settled and long hair tied back.
- Closed-toe shoes and a lab coat or apron; no loose clothing near the bench.
- The bench wiped down and cleared of everything not needed for today's experiment.
- The room well ventilated, and any spill of water or materials wiped up right away.
- Paper towels, a waste bin, and a first-aid kit located — you know where each one is before you start.
- Clean-up plan clear — you know exactly where each tool and leftover material goes when you finish.
2 — Setup
With safety confirmed, build the bench so the work flows without scrambling mid-experiment.
- The full procedure read end to end — not skimmed — so you know what step comes next.
- All tools gathered, clean, and dry (unless the procedure calls for water) and laid out in order of use.
- The right measuring tool — ruler, balance, stopwatch, or graduated cylinder — selected to match the precision the step requires.
- Balance located and tared; you know which masses you need to record and to how many decimal places.
- Materials located, labels double-checked against the procedure, and quantities confirmed.
- Any timing or measuring setup arranged safely — the workspace clear so nothing gets knocked over mid-run.
- Lab notebook open to a fresh, dated page with the title and question already written.
3 — Readiness: the pre-lab questions
This is the section that separates a button-pusher from a scientist. Before the first measurement, the student should be able to answer these in writing — in the lab notebook, in their own words.
- What is the question? State, in one sentence, what this experiment is trying to find out or measure.
- What is the plan? Write, in one line, exactly what you will change, what you will keep the same, and what you will measure.
- What is my prediction? A specific, numerical expectation — roughly how far, how long, how much, and in which direction.
- What am I measuring, and in what units? Name every quantity you will record, its unit, and its uncertainty.
- What could go wrong? Identify the one or two steps most likely to introduce error, and how you will minimize them.
- What does success look like? Know, before you begin, what a reasonable result would be — so an absurd number raises a flag right away, not a week later.
A student who answers all six is not guessing their way through a recipe — they are running an experiment they understand, with a result they can already roughly predict. That is exactly the readiness the lab-notebook entry is built to capture, and the kind of preparation a lab defense is designed to reward.