The idea for this one came from watching a small child try to balance painted story stones on top of each other. The stones in question were not designed to stack, but a determined toddler had decided otherwise. It looked like a tiny, wobbly cairn. So I went down to the garden with a bucket, hunted out twelve smooth stones in graduating sizes, and turned them into two proper stacking sets, painted in the colors of a rainbow. The result is a sit-on-the-floor stacking activity that doubles as a small lesson in keep-trying. Ages 2 to 5.
Finding the stones
The single most important thing is that the stones can actually stack. That means a flat-ish bottom and a flat-ish top on each one. Round pebbles will roll off each other and the whole activity dissolves into stones-on-the-floor. The best hunting grounds are gravel piles, garden borders, dry river beds, and beaches. Take more than you think you need and bring them home to test.
The full rainbow has seven colors. The stacking version, in our experience, has six. We tried to make a seven-stone tower and not once did all seven stay up. Six is achievable: red, orange, yellow, green, blue, purple. The biggest stone is red, on the bottom, and they shrink up to a small purple on top.
What you need
- Six smooth stones in graduating sizes for one set, or twelve for two sets. The biggest stone should fit comfortably in an adult palm.
- A small set of acrylic paints in the rainbow colors. Cheap craft-aisle tubes are fine.
- A small paintbrush.
- A pot of decoupage glue, or white craft glue thinned slightly with water, for sealing.
- Newspaper or a scrap of cardboard to paint on.
Painting them
Wash the stones in warm soapy water and let them dry overnight. Acrylic paint does not stick well to dust or oil.
Paint each stone with the color it has been assigned. Acrylic needs at least two coats to look solid, and yellow specifically needs three or four. Paint one side, let it dry, flip and paint the other side, repeat. The fiddly bit is the very edge. Work the brush around the rim so the color reads from any angle.
Once the paint is dry, brush a thin coat of decoupage glue over each stone. This is what saves you from chipped paint when the stones knock together later. The glue goes on milky and dries clear, leaving the stones with a soft sheen.
Stacking, and the falling
This is harder than it looks. The first time a small child tries, the tower will fall on the second stone. Probably the first. Then it will fall again. The trick that makes the activity actually work is built into the demonstration: when you show a child how to stack, knock the tower over a few times on purpose. Laugh. Say “let me try again”. That sets the rule from the start. Falling is part of the activity, not a failure.
From there it is a quiet kind of focus. Pick the biggest stone, put it down flat. Find the next-biggest. Lower it slowly until it sits. Hold for a second to make sure it has settled. Next color. The wrist has to be steady, the eyes have to stay on the contact point, and the hand has to let go without dragging. All the fine motor work that shows up later in handwriting is hiding in this activity.
Round versus flat
Our two sets ended up with different personalities. One was made of rounded river-pebble stones, the other from flatter slate-like ones. The flat stones are noticeably easier to stack and end up taller, faster. The rounded stones are harder, take more care, and topple more, but the tower has a better look when it stays up. We use the flat set for early tries and the rounded set when a child wants more of a challenge.
Why they keep coming back
The stones live in a small cloth bag on a shelf and come out a few times a week. The activity scales: at two, a child stacks two or three stones and is delighted. At four, the whole tower goes up and the satisfaction is enormous. The paint and glue have held up to several years of stacking, dropping, and being carried around the house in pockets. Stones outlast plastic.
For another stone-based play set that uses painted river pebbles, our penguin story stones turn the same kind of stones into characters for retelling a winter story. And for a quieter sit-down option in the same age band, our free summer coloring pages give a child something to color when the stones go back in the bag.