diff --git a/session_gems/lab/03-Pathway-visualization.ipynb b/session_gems/lab/03-Pathway-visualization.ipynb
index 056e3ad..7fa2479 100644
--- a/session_gems/lab/03-Pathway-visualization.ipynb
+++ b/session_gems/lab/03-Pathway-visualization.ipynb
@@ -56,7 +56,8 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "escher.Builder('e_coli_core.Core metabolism')"
+    "b = escher.Builder('e_coli_core.Core metabolism')\n",
+    "escher.Builder.save_html(b, filepath='data/Ecoli_core_03')"
    ]
   },
   {
@@ -72,9 +73,10 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "escher.Builder('e_coli_core.Core metabolism',\n",
+    "b = escher.Builder('e_coli_core.Core metabolism',\n",
     "               reaction_data={'PGK': 100},\n",
-    "               metabolite_data={'ATP': 20})"
+    "               metabolite_data={'ATP': 20})\n",
+    "escher.Builder.save_html(b, filepath='data/Ecoli_core_031')"
    ]
   },
   {