Fun with Coloring-for-Kids.com: Summer Coloring page – Sandcastle – online game by numbers, letters or download and paint with brushes. Choose a coloring mode, from standard coloring using a wide range of tools, to a game by numbers that children will enjoy and improve attention. The result of the painstaking work of the young artist can be shared on social networks through the site. Creative Commons Attribution-NonCommercial 4.0 License. Author of the work: Persimmons Studio.