admincontroller

var studentModel = require('../models/Student');

student_new: function(req, res){
			var student = new studentModel({ name: 'Nicholas' });
			student.save(function (err) {
			   if (err) // ...
			   console.log('CADASTROUUU');
			 });
			res.render('admin/student/new');
		},

coreMODEL

var mongoose = require('mongoose'), 
	db, 
	schema = mongoose.Schema;;

mongoose.connect('mongodb://localhost/moodle');

db = mongoose.connection;

db.on('error', console.error);
db.once('open', function() {
	console.log("mongo on");
});
var model = {
	Schema: schema,
	db: db 
};

module.exports = model;

modelsSTUDENT

var mongoose = require('../lib/core/model'),
	Schema = mongoose.Schema,
	mongo = mongoose.db;

var student = new Schema({
    name: String
})

module.exports = mongo.model('student', student);