diff --git a/.github/workflows/svf-teaching.yml b/.github/workflows/svf-teaching.yml
index 946a80a..7db1de5 100644
--- a/.github/workflows/svf-teaching.yml
+++ b/.github/workflows/svf-teaching.yml
@@ -8,7 +8,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-18.04, macos-11]
+        os: [ubuntu-20.04, macos-11]
     steps:
       # checkout the repo
       - uses: actions/checkout@v2