My Building

Hey i'm trying to make my school 3D model, but i don't know nothing of Blender, 3DS Max, Milkshpae and stuff. Is there a way to make this model just using nodes in jme??

Well, yes node,s trimeshes and primitive objects are possible, however before you get a acceptable result you probably learned how to model using a programm, since it is kinda like programming  in assembler, working but slow and annoying as hell.

Well, nodes are not geometry just by themselves (they can be purely logical or help define transformations for geometry (e.g. pivot points)).

Procedural mesh creation is tedious, difficult, and you're just not going to get the sort of results if you created the art manually (some things are fine if you procedurally create them, for most models not so much). It would be infinitely easier getting a free modeling tool and learning how to create models yourself.

Here's a page on the wiki detailing a list of common modeling suites (many which are free) that you could try: