diff --git a/examples/pd_grid/pd_grid/model.py b/examples/pd_grid/pd_grid/model.py
index 1be0d4fc..b1c2a05c 100644
--- a/examples/pd_grid/pd_grid/model.py
+++ b/examples/pd_grid/pd_grid/model.py
@@ -6,11 +6,7 @@
 class PdGrid(mesa.Model):
     """Model class for iterated, spatial prisoner's dilemma model."""
 
-    schedule_types = {
-        "Sequential": mesa.time.BaseScheduler,
-        "Random": mesa.time.RandomActivation,
-        "Simultaneous": mesa.time.SimultaneousActivation,
-    }
+    activation_regimes = ["Sequential", "Random", "Simultaneous"]
 
     # This dictionary holds the payoff for this agent,
     # keyed on: (my_move, other_move)
diff --git a/examples/pd_grid/pd_grid/server.py b/examples/pd_grid/pd_grid/server.py
index 1709fcce..57785acc 100644
--- a/examples/pd_grid/pd_grid/server.py
+++ b/examples/pd_grid/pd_grid/server.py
@@ -10,9 +10,9 @@
     "height": 50,
     "width": 50,
     "activation_order": mesa.visualization.Choice(
-        "Scheduler type",
+        "Activation regime",
         value="Random",
-        choices=list(PdGrid.schedule_types.keys()),
+        choices=PdGrid.activation_regimes,
     ),
 }