Science Experiments for 8-Year-Olds

By eight, many children can follow a short plan, measure with a ruler and keep notes. They also start to care about being right, which is a good moment to teach them that a surprising result is more interesting than a correct guess.

These experiments suit anyone teaching a child this age, whether at home, in a co-op or one-to-one. Most need only household items. An adult should handle anything sharp or hot, and nothing is for eating.

The one skill to teach: fair testing

A fair test changes one thing and keeps everything else the same. Before each experiment ask: “What are we changing? What must stay the same? What will we measure?” Write the three answers at the top of the page. It is the most useful habit you can build at this age.

1. Magnets through a barrier

Test whether a magnet can pull a paper clip through paper, cardboard, a plastic tray and a wooden board. Stack extra sheets of paper until it stops working, and count the sheets. The post on magnet experiments through a table has the method, and the lesson Can a magnet work through a table? turns it into a full investigation.

2. Paper plane fair test

Make three planes from identical paper with different wing shapes. Launch each one five times from the same line and measure the distance with a tape measure or a metre stick. Average the five throws. Who throws matters, so let the same person throw every time. See the paper airplane experiment for a worked example.

3. Which surface is slipperiest?

Tilt a wooden board on a pile of books. Slide a small block down different surfaces: sandpaper, cloth, plastic wrap, bare wood. Raise the board a little at a time and note the height where the block starts to slide. Your child is measuring friction without needing the word, though it is a good moment to introduce it.

4. Do plants bend toward light?

Plant two bean seeds in cups. Put one on a sunny windowsill and place the other in a cardboard box with a small hole on one side. After a week, compare. The one in the box should lean toward the hole. Draw each plant every two days. Our lesson Why do plants grow toward the window? covers the same idea.

5. How fast does ice melt?

Put an ice cube of the same size in each of three cups: one on a metal tray, one on a wooden board, one wrapped in a woollen sock. Check every five minutes and record how much is left. Ask which material is the best insulator, and which one feels cold to touch even though it is the same temperature as the others.

6. Reaction time with a ruler

One person holds a 30 cm (12 in) ruler at the top. The other places a thumb and finger at the zero mark, without touching. Drop the ruler without warning and catch it. The distance fallen shows how fast you reacted. Do ten attempts each and compare. Our blog post on the ruler-drop reaction time explains how to use the numbers.

Helping them record

A simple two-column table is enough: what we changed, what we measured.
Use centimetres, seconds and counts.
Draw a quick bar chart from the numbers. Bars are the easiest graph to read at this age.
Ask “How do you know?” more often than “What happened?”

When it gets competitive

If children are racing or comparing results with a friend, remind them that the aim is to find out, not to win. Repeat anything where the results are close. “Let us try that again to be sure” is a sentence worth hearing in your home.

Where to go next

Look at the unit forces and magnets for a connected sequence, and the measure it unit for practice with units and estimating. If you are choosing lessons for a mixed-age group, science with children of different ages together is worth a read.