Translucent color blocks are gorgeous on a light box, but the shop-bought sets are surprisingly pricey. These homemade ones cost a fraction of that: plain wooden blocks, a few sheets of colored cellophane, and a glue gun. Stack them, look through them, and watch the colors glow and mix wherever the light shines through. Ages 2 to 5.
Making the blocks
Open-fronted wooden blocks work best, the kind that are a square or rectangular frame, so the light can shine straight through. Cut a piece of colored cellophane or acetate to fit each opening and fix it in place with a dab of hot glue. The glue gun is firmly a grown-up job. A pack of inexpensive wooden blocks and a few colors of cellophane will make a whole set.
If you do not have framed blocks, you can tape squares of cellophane over the gaps in any chunky open blocks, or simply use loose cellophane squares on their own.
How it plays
The magic happens with light behind them. A light box is ideal, but a sunny window, a string of fairy lights, or a torch underneath all work just as well. Suddenly the blocks glow, and a child can hold one up to look through, lay them on the light to see the colors pool, and stack them up into glowing towers.
The best discovery is color mixing: overlap a blue block and a yellow one and the patch where they meet turns green. Red over blue makes purple. Working out which colors make which, just by stacking, is early color theory and the kind of thing children will test again and again.
They double as ordinary building blocks when the light goes off, so they earn their place in the toy box. It is calm, absorbing play that looks beautiful and quietly teaches a lot about light and color.
For more colorful play, our taste-safe rainbow sensory play explores color through touch, and our night time glow in the dark bowling is another way to play once the lights are off.