What you'll need:
Paper (various colours)
Buttons (red or a colour of your choice)
Double sided tape
Cut the black paper into a rectangle, the white paper into a circle and the red paper into a strip.
Stick the three pieces of paper together as follows and glue the buttons onto the red strip of paper. Draw a face on the white circle (snowman).
Cut three circles in defending size order out of the white paper. Cut arms out of the black paper and two triangles out of a coloured piece of pear.
Draw a face on the smallest circle. Using the double sided tape stick the circles on top of one another. Add the arms to the bottom circle and the two triangles on the second circle (to look like a bow tie).
Out of some multi-coloured paper or green paper draw a big triangle and then cut diagonal lines out of the tree.
On white paper stick the strips together as follows. To form a slanted Christmas tree.
There you have it, all three Christmas cards, as easy as that.