Simple Science Investigations for Preschoolers

Young children are born scientists. They drop spoons to see what happens, ask "why?" a hundred times a day, and are endlessly fascinated by bugs, water and mud. Preschool science isn't about memorizing facts — it's about nurturing that curiosity and giving children the tools to investigate the world.

Here's how to bring real science into your classroom or home, with investigations that use simple, inexpensive materials.

The science process for little learners

Even three- and four-year-olds can practice the steps scientists use:

1. Wonder: ask a question. "What will happen if…?"
2. Predict: make a guess. "I think it will sink."
3. Test: try it out.
4. Observe: notice what happens.
5. Talk about it: "It floated! Why do you think it floated?"

Record predictions and results on a simple chart with pictures or tally marks. Children love seeing their predictions written down, and it introduces early data collection.

Investigations to try

Sink or float

Fill a tub with water and gather a mix of objects: a rock, a cork, a spoon, a leaf, a toy car, an apple, a crayon. Before each test, children predict. Sort results onto two trays. Then challenge them: "Can you make the foil float? Can you make it sink?"

Ramps and rolling

Lean a board against blocks to make a ramp. Which objects roll fastest? Does a steeper ramp make cars go farther? What rolls and what slides? This investigation is perfect for the block center.

Magnet exploration

Give children magnets and a tray of objects. Which ones stick? Sort into "magnetic" and "not magnetic." Children often assume all metal is magnetic — testing coins, foil and paper clips makes for interesting surprises.

Melting ice

Freeze small toys in ice. Children predict how to get them out fastest — salt, warm water, sunlight, holding it? Test each idea.

Color mixing

Give children droppers and cups of red, yellow and blue water. Predict what happens when colors mix, then try it. Record the results: red + yellow = orange!

Growing seeds

Plant bean seeds in a clear cup with a wet paper towel so children can see roots grow. Measure the plant each few days with linking cubes and chart its growth.

Shadows

On a sunny day, trace children's shadows with chalk in the morning, then again at midday. What changed? Indoors, use a flashlight to make shadow puppets and explore how moving the light changes the shadow.

Bubbles

Make bubble solution and try different wands: straws, pipe cleaners, slotted spoons, cookie cutters. Does the wand shape change the bubble shape?

Apple investigation

In the fall, explore apples: weigh them, measure around them with string, predict how many seeds are inside, cut them open and count. Compare red, green and yellow apples in a taste test and graph the class favorite.

Five senses walk

Take a walk and use each sense: What do you see? Hear? Smell? What does the bark feel like? Record findings with drawings.

Nature collection and sorting

Collect leaves, rocks and sticks. Examine them with magnifying glasses. Sort by size, color or texture. Leave a collection in the science center for continued exploration.

Weather watchers

Keep a simple daily weather chart. Set a rain gauge outside. At the end of the month, count sunny, cloudy and rainy days.

Setting up a science center

A small science area invites ongoing exploration:

• Magnifying glasses and a magnifying box for bugs
• A bucket balance
• Magnets of different kinds
• Measuring tools: cups, spoons, measuring tape
• Natural objects that change with the seasons
• A plant or two children can care for
• Clipboards and paper for recording observations
• Nonfiction books related to the current topic

Rotate items with your themes so there's always something new to discover.

Ask great questions

The questions you ask matter more than the activity. Try:

• "What do you notice?"
• "What do you think will happen?"
• "Why do you think that happened?"
• "How could we find out?"
• "What would happen if we changed…?"

And when children ask you something you don't know, the best answer is often, "I don't know. How could we find out?"

Science words to introduce

Predict, observe, experiment, investigate, compare, measure, float, sink, magnet, melt, freeze, dissolve, texture, shadow, roots, stem, living, nonliving. Children love using "big" science words, and they learn them quickly in context.

Safety tips

• Supervise water play and small objects closely.
• Check for allergies before any food investigation.
• Wash hands after handling soil, plants and animals.
• Teach children to observe insects gently and return them outside.

For homeschool families

The kitchen is a wonderful science lab. Baking shows how ingredients change when heated. Freezing juice pops shows liquids becoming solids. A walk around the neighborhood is a nature study. Keep a family science notebook with drawings and dictated observations — it becomes a treasured record of your child's discoveries.

Science connects naturally to math and play. See teaching measurement and sensory bins 101 for related activities.

Frequently asked questions

Do I need a science kit for preschool?

No. Most of the best preschool investigations use water, magnets, ice, seeds, magnifying glasses and objects from around the house or outdoors.

What if the experiment doesn't 'work'?

That's science! Ask children why they think it turned out differently than expected and what they could change next time. Surprises lead to the best conversations.