It is so easy for drawing a moon for children because there are no critical steps for to make the moon. There are only two just steps for make a moon with two curve and these two steps are given below with the picture .
In the 1 st step, make a curve as like in the above picture no 1.
And in the next step, make another curve like picture no 1 with no 2 which will be joint the 1st and last point of no 1 curve as it is shown in the picture no 2.
After theses two step made the drawing of moon is now ready for the color.You can add your choice of color it the moon and its background or also you can add black in the background, as it is given in the picture below. And after added color your drawing is ready now.