It is a great idea because colouring activities enhance their creativity skills. But It will be more creative if we add worksheets and some IQ games with colouring. As Christmas is coming so, it will be more easy to engage your child with different activities. I would suggest you a wonderful site https://wunderkiddy.com/material/decorating-the-christmas-tree here are lots of learning activities colouring pages as well specially for Christmas. You should try this for your child.