vm.studentEnrollmentChecked = studentEnrollmentChecked;
        function studentEnrollmentChecked(obj) {

            if(obj.checked) {

                // verifica se obj.token existe dentro do array vm.form.students, caso não existir adicione a copia do obj junto ao vm.form.students

                let studentIn = false;

                angular.forEach(vm.form.students, function(objArr, key) {
                    if(obj.token === objArr.token) {
                        studentIn = true;
                    }
                });

                if(!studentIn) {
                    vm.form.students.push(obj);
                }

            } else {

                // verifica se existe no vm.form.students, caso existir remover o elemento do array vm.form.students

                let studentIn = false;

                angular.forEach(vm.form.students, function(objArr, key) {
                    if(obj.token === objArr.token) {
                        studentIn = true;
                    }
                });

                if(studentIn) {
                    vm.form.students.splice(obj, 1);
                }

            }

            console.log('vm.form.students', vm.form.students);
        }