diff --git a/backend/src/controllers/studentMaterialsController.js b/backend/src/controllers/studentMaterialsController.js
index cc89127..7d06dc3 100644
--- a/backend/src/controllers/studentMaterialsController.js
+++ b/backend/src/controllers/studentMaterialsController.js
@@ -66,7 +66,7 @@ function create(req, res) {
 }
 
 /* PATCH /api/materials/:id — rename / edit one of the current user's items.
-   Editable: title, body. (collection_id/tags wired in a later phase.) */
+   Editable: title, body, url (e.g. re-saving an annotated image), collection_id, tags. */
 function update(req, res) {
   const row = db.prepare('SELECT user_id FROM student_materials WHERE id = ?').get(req.params.id);
   if (!row) return res.status(404).json({ error: 'not found' });
@@ -75,6 +75,7 @@ function update(req, res) {
   const fields = [], args = [];
   if (b.title !== undefined) { fields.push('title = ?'); args.push(String(b.title || '').slice(0, 300)); }
   if (b.body  !== undefined) { fields.push('body = ?');  args.push(b.body != null ? String(b.body).slice(0, 60000) : null); }
+  if (b.url   !== undefined) { fields.push('url = ?');   args.push(b.url != null ? String(b.url).slice(0, 2000) : null); }
   if (b.collection_id !== undefined) { fields.push('collection_id = ?'); args.push(ownCollectionId(b.collection_id, req.user.id)); }
   if (b.tags !== undefined) { fields.push('tags = ?'); args.push(b.tags != null ? String(b.tags).slice(0, 500) : null); }
   if (!fields.length) return res.json({ ok: true });
diff --git a/frontend/my-materials.html b/frontend/my-materials.html
index d70b9f6..aa7d30e 100644
--- a/frontend/my-materials.html
+++ b/frontend/my-materials.html
@@ -412,8 +412,14 @@
           if (!blob) throw new Error('Не удалось сохранить рисунок');
           const fd = new FormData(); fd.append('file', blob, 'drawing.png');
           const up = await LS.uploadMaterialFile(fd);
-          await LS.saveMaterial({ kind: 'image', title: o.title || 'Рисунок', url: up.url, sourceTitle: o.sourceTitle || null });
-          close(); load(); LS.toast('Сохранено в «Мои материалы»', 'success');
+          if (o.materialId) {
+            // Аннотация существующего материала — перезаписываем его, а не плодим копии
+            await LS.updateMaterial(o.materialId, { url: up.url });
+            close(); load(); LS.toast('Изменения сохранены', 'success');
+          } else {
+            await LS.saveMaterial({ kind: 'image', title: o.title || 'Рисунок', url: up.url, sourceTitle: o.sourceTitle || null });
+            close(); load(); LS.toast('Сохранено в «Мои материалы»', 'success');
+          }
         } catch (e) { LS.toast(e.message || 'Ошибка', 'error'); btn.disabled = false; }
       });
     };
@@ -423,7 +429,7 @@
   function annotate(id) {
     const mt = _mats.find(x => x.id === id);
     if (!mt) return;
-    openDrawModal({ bgImage: mt.url, title: (mt.title || 'Рисунок') + ' (разметка)', sourceTitle: mt.source_title });
+    openDrawModal({ materialId: mt.id, bgImage: mt.url, title: mt.title || 'Рисунок', sourceTitle: mt.source_title });
   }
   window.annotate = annotate;