diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 0d9d338..e3b6f4d 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -12,11 +12,11 @@ jobs:
     strategy:
       matrix:
         python-version:
-          - 3.6
-          - 3.7
-          - 3.8
-          - 3.9
-          - 3.10
+          - '3.6'
+          - '3.7'
+          - '3.8'
+          - '3.9'
+          - '3.10'
 
     name: Python ${{ matrix.python-version }}
     steps: