Data table
01 // Build it before you collect data
A data table works best when it's built before an experiment starts, not scribbled together afterward from scattered notes. Planning the table first forces you to think through exactly what you're changing, what you're measuring, and how many trials you'll run — which is really just the variables section of your experiment turned into a grid.
02 // How to set one up
1. Independent variable first
Put the thing you're changing on purpose in the leftmost column.
2. Units in the header, not every cell
Write the unit once in the column header, like "Mass (g)", instead of repeating it in every row.
3. One row per trial
Give every trial its own row so repeated measurements are easy to compare and average.
4. Leave room for calculated columns
Add columns for anything you'll calculate afterward, like an average or percent change, so the table stays in one place.
03 // Weak table vs. clear table
| Weak version | Clear version |
|---|---|
| Trial 1: 12g, Trial 2: 11.8g... | Rows and columns, one value per cell |
| "grams" repeated in every cell | "Mass (g)" written once, in the header |
| No title or units on the table | Title states exactly what's being measured |
| Independent variable buried mid-table | Independent variable in the leftmost column |
04 // Questions people ask
Which variable goes in the first column of a data table?
The independent variable — the one you are deliberately changing — belongs in the leftmost column. The dependent variable, what you measure in response, goes in the columns to its right.
Where should units go in a data table?
Units belong once, in the column header, such as "Volume (mL)" — not repeated after every individual number in the column. This keeps the table easier to read and less cluttered.
Why build the data table before starting the experiment?
Planning the table first forces you to clearly define your variables and decide how many trials you'll run before you start collecting data, which prevents scrambling to organize scattered numbers after the fact.