I have made this up myself and if anyone else has made it already, I don't know.
This is modular origami.
So, here we go!

Step 1: Materials and Tools

To make this you need:
6 pieces of paper,
glue,
a pencil,
a ruler,
and scissors.

Step 2: Step One

The pictures will hopefully help you understand what to do.
Cut the paper in half and put one half off to the side for now fold the other half like pictures 2 and 3.
Now fold like pictures 3,4,5, and 6.
Now you need to fold it like pictures7,8,9,10, and 11.
Repeat this on back.

Step 3: Step Two

You really only need to follow the pictures and repeat steps one and two on four more papers and on the other half of this one.

Step 4: Step Three

Stack them up like the pictures show.
The top is now done.
You only have the trunk left.

Step 5: Step Four

Measure four inches along the short edge of the paper and cut it there.
Take the longer piece and roll it up as shown.
Then glue or tape it shut.
Then take one of the pieces of the tree and glue the stick in to it.
Use the ruler to make a mark on the stick where the bottom points of the triangle are.
Just cut there.

Step 6: Done!

Make sure the trunk is lined up with the bottom of the tree.
Once everything is dry, you have your very own christmas tree!
The leaves will also come off to make it shorter or you can make more to make it taller.