diff --git a/app/controllers/courses_controller.rb b/app/controllers/courses_controller.rb
index 0bb027153..e3d7c9d06 100644
--- a/app/controllers/courses_controller.rb
+++ b/app/controllers/courses_controller.rb
@@ -561,6 +561,7 @@ class CoursesController < ApplicationController
   def delete_member
     member = @course.members.find params[:member_id]
     student_role = member.member_roles.where("role_id = 10").first
+    teacher_role = member.member_roles.where("role_id = 7 || role_id = 9").first
     if member && member.deletable? && student_role
       user_admin = CourseInfos.where("user_id = ? and course_id = ?", member.user_id, @course.id)
       if user_admin.size > 0
@@ -569,8 +570,9 @@ class CoursesController < ApplicationController
       joined = StudentsForCourse.where('student_id = ? and course_id = ?', member.user_id,@course.id)
       joined.destroy_all
 
-      if member.member_roles.count > 1
+      if member.member_roles.count > 1&& student_role && teacher_role
         student_role.destroy
+        teacher_role.update_attribute("is_current", 1)
         member.update_attribute("course_group_id", 0)
       else
         member.destroy
diff --git a/app/models/homework_common.rb b/app/models/homework_common.rb
index c87cd3d42..3690df1f3 100644
--- a/app/models/homework_common.rb
+++ b/app/models/homework_common.rb
@@ -15,7 +15,7 @@ class HomeworkCommon < ActiveRecord::Base
   has_one :homework_detail_group, :dependent => :destroy
   has_many :student_work_projects, :dependent => :destroy
   has_many :homework_tests, :dependent => :destroy
-  has_many :student_works, :dependent => :destroy, :conditions => "is_test=0"
+  has_many :student_works, :dependent => :destroy, :conditions => "is_test=0 and is_delete != 1"
   has_many :student_works_evaluation_distributions, :through => :student_works #一个作业的分配的匿评列表
   has_many :journals_for_messages, :as => :jour, :dependent => :destroy
   has_many :apply_homeworks, :dependent => :destroy
diff --git a/app/models/students_for_course.rb b/app/models/students_for_course.rb
index 767d65b10..d9bf96770 100644
--- a/app/models/students_for_course.rb
+++ b/app/models/students_for_course.rb
@@ -9,11 +9,21 @@ class StudentsForCourse < ActiveRecord::Base
   validates_uniqueness_of :student_id, :scope => :course_id
 
   after_destroy :delete_student_works
+  after_create :recovery_student_works
 
+  #退出班级或删除学生时隐藏学生的作品
   def delete_student_works
     course = self.course
     homework_ids = course.homework_commons.blank? ? "(-1)" : "(" + course.homework_commons.map{|hw| hw.id}.join(",") + ")"
     student_works = StudentWork.where("user_id = #{self.student_id} && homework_common_id in #{homework_ids}")
-    student_works.destroy_all
+    student_works.update_all(:is_delete => 1)
+  end
+
+  #加入班级时还原作品
+  def recovery_student_works
+    course = self.course
+    homework_ids = course.homework_commons.blank? ? "(-1)" : "(" + course.homework_commons.map{|hw| hw.id}.join(",") + ")"
+    student_works = StudentWork.where("user_id = #{self.student_id} && homework_common_id in #{homework_ids}")
+    student_works.update_all(:is_delete => 0)
   end
 end
diff --git a/app/services/courses_service.rb b/app/services/courses_service.rb
index f72623d84..43bdf9e09 100644
--- a/app/services/courses_service.rb
+++ b/app/services/courses_service.rb
@@ -452,12 +452,20 @@ class CoursesService
       @state = 2
       return @state
     end
-    @member = Member.where('course_id = ? and user_id = ?', params[:object_id], user.id)
-    if @member.nil? || @member.count == 0
+    @member = Member.where('course_id = ? and user_id = ?', params[:object_id], user.id).first
+    if @member.nil?
       @state = 1
       return @state
     end
-    @member.first.destroy
+    student_role = @member.member_roles.where("role_id = 10").first
+    teacher_role = @member.member_roles.where("role_id = 7 || role_id = 9").first
+    if @member.member_roles.count > 1 && student_role && teacher_role
+      student_role.destroy
+      teacher_role.update_attribute("is_current", 1)
+      @member.update_attribute("course_group_id", 0)
+    else
+      @member.destroy
+    end
     joined = StudentsForCourse.where('student_id = ? and course_id = ?', user.id, params[:object_id])
     joined.each do |join|
       join.destroy
diff --git a/app/views/courses/_set_join.js.erb b/app/views/courses/_set_join.js.erb
index 822757dfe..7c395e54e 100644
--- a/app/views/courses/_set_join.js.erb
+++ b/app/views/courses/_set_join.js.erb
@@ -1,3 +1,4 @@
+hideModal();
 <% if object_id && @state != 6%>
     $("#join_in_course_header").html("<%= escape_javascript(join_in_course_header(course, user)) %>");
 <% end %>
diff --git a/app/views/layouts/_course_base_info.html.erb b/app/views/layouts/_course_base_info.html.erb
index e3041f92c..3b1c70fe8 100644
--- a/app/views/layouts/_course_base_info.html.erb
+++ b/app/views/layouts/_course_base_info.html.erb
@@ -26,6 +26,18 @@
         </li>
       </ul>
     </div>
+<% elsif User.current.logged? && User.current.member_of_course?(@course) %>
+    <div class="sy_class_setting" >
+      <ul>
+        <li class="sy_class_setting_icon">
+          <ul class="sy_class_setting_text">
+            <li>
+              <a href="javascript:void(0)" onclick="delete_confirm();" class="sy_class_option">退出班级</a>
+            </li>
+          </ul>
+        </li>
+      </ul>
+    </div>
 <% end %>
 
 <div class="cl"></div>
@@ -84,7 +96,7 @@
   <% elsif is_teacher && is_ST %>
       <%= link_to '学生身份', switch_role_course_path(@course, :user_id => User.current.id, :curr_role => (is_TA ? 7 : 9), :tar_role => 10), :class => "sy_btn_orange mr10 fl", :title => "由教师身份切换至学生身份" %>
   <% end %>
-  <% unless (is_teacher || is_TA || is_TE) %>
+  <% unless (is_teacher || is_TA || is_TE || is_ST) %>
       <div id="join_in_course_header"><%= join_in_course_header(@course, User.current) %></div>
   <% end %>
 </div>
diff --git a/app/views/layouts/base_courses.html.erb b/app/views/layouts/base_courses.html.erb
index 19f7694b3..957f720be 100644
--- a/app/views/layouts/base_courses.html.erb
+++ b/app/views/layouts/base_courses.html.erb
@@ -276,6 +276,13 @@
        $("#expand_tools_expand a").addClass('active');
        $("#navContentCourse").toggle();
     });
+
+    function delete_confirm(){
+        var htmlvalue = '<div id="muban_popup_box" style="width:300px;"><div class="muban_popup_top"><h3 class="fl">提示</h3><a href="javascript:void(0);" class="muban_icons_close fr"></a></div>'+
+                '<div class="clear mt15"><p class="text_c f14">您确认要退出该班级吗？</p><div class="cl"></div><a href="<%=join_path(:object_id => @course.id) %>" class="fr sy_btn_blue mr85 mt10" data-method="delete" data-remote="true">确&nbsp;&nbsp;定</a>'+
+                '<a href="javascript:void(0);" class="fr sy_btn_grey mt10 mr10" onclick="hideModal();">取&nbsp;&nbsp;消</a></div></div>';
+        pop_box_new(htmlvalue, 300, 140);
+    }
 </script>
 
 </html>
\ No newline at end of file
diff --git a/db/migrate/20161117015856_add_is_delete_to_student_works.rb b/db/migrate/20161117015856_add_is_delete_to_student_works.rb
new file mode 100644
index 000000000..f6b3abdd6
--- /dev/null
+++ b/db/migrate/20161117015856_add_is_delete_to_student_works.rb
@@ -0,0 +1,5 @@
+class AddIsDeleteToStudentWorks < ActiveRecord::Migration
+  def change
+    add_column :student_works, :is_delete, :integer, :default => 0
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index fd75bb020..b95fd7a56 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20161114092115) do
+ActiveRecord::Schema.define(:version => 20161117015856) do
 
   create_table "activities", :force => true do |t|
     t.integer  "act_id",                                  :null => false
@@ -1910,6 +1910,7 @@ ActiveRecord::Schema.define(:version => 20161114092115) do
     t.float    "work_score"
     t.integer  "work_status",                                   :default => 0
     t.datetime "commit_time"
+    t.integer  "is_delete",                                     :default => 0
   end
 
   add_index "student_works", ["homework_common_id", "user_id"], :name => "index_student_works_on_homework_common_id_and_user_id"
diff --git a/public/stylesheets/css/common.css b/public/stylesheets/css/common.css
index afe6192fb..08d12745d 100644
--- a/public/stylesheets/css/common.css
+++ b/public/stylesheets/css/common.css
@@ -169,6 +169,7 @@ h4{ font-size:14px;}/*color:#3b3b3b;*/
 .mr70{margin-right: 70px;}
 .mr75{margin-right: 75px;}
 .mr80{margin-right: 80px;}
+.mr85{margin-right: 85px;}
 .mr95 {margin-right:95px !important;}
 .mr100 {margin-right:100px !important;}
 .mr118 {margin-right:118px !important;}