The lovely Bhutan flag features the Thunder Dragon, the emblem of the country, on a yellow and orange background. Here's a colouring page for the kids.
Bhutan Flag Colouring Page
Here's a colouring flag of Oman to print for the kids. The central and left section is a bright red, while the crest stays white and the bottom section is green.
Here is a colouring page of the Bahrain flag, ready to be coloured in with its striking red and white design.