diff --git a/wpilibNewCommands/src/test/java/edu/wpi/first/wpilibj2/command/SchedulerTest.java b/wpilibNewCommands/src/test/java/edu/wpi/first/wpilibj2/command/SchedulerTest.java
index 7a62f5ea27..ee1f8eb37c 100644
--- a/wpilibNewCommands/src/test/java/edu/wpi/first/wpilibj2/command/SchedulerTest.java
+++ b/wpilibNewCommands/src/test/java/edu/wpi/first/wpilibj2/command/SchedulerTest.java
@@ -43,13 +43,41 @@ class SchedulerTest extends CommandTestBase {
     }
   }
 
+  @Test
+  void registerSubsystemTest() {
+    try (CommandScheduler scheduler = new CommandScheduler()) {
+      AtomicInteger counter = new AtomicInteger(0);
+      Subsystem system =
+          new SubsystemBase() {
+            @Override
+            public void periodic() {
+              counter.incrementAndGet();
+            }
+          };
+
+      assertDoesNotThrow(() -> scheduler.registerSubsystem(system));
+
+      scheduler.run();
+      assertEquals(1, counter.get());
+    }
+  }
+
   @Test
   void unregisterSubsystemTest() {
     try (CommandScheduler scheduler = new CommandScheduler()) {
-      Subsystem system = new SubsystemBase() {};
-
+      AtomicInteger counter = new AtomicInteger(0);
+      Subsystem system =
+          new SubsystemBase() {
+            @Override
+            public void periodic() {
+              counter.incrementAndGet();
+            }
+          };
       scheduler.registerSubsystem(system);
       assertDoesNotThrow(() -> scheduler.unregisterSubsystem(system));
+
+      scheduler.run();
+      assertEquals(0, counter.get());
     }
   }
 
diff --git a/wpilibNewCommands/src/test/native/cpp/frc2/command/CommandTestBase.h b/wpilibNewCommands/src/test/native/cpp/frc2/command/CommandTestBase.h
index 035f5dedbf..1e4e5f7123 100644
--- a/wpilibNewCommands/src/test/native/cpp/frc2/command/CommandTestBase.h
+++ b/wpilibNewCommands/src/test/native/cpp/frc2/command/CommandTestBase.h
@@ -19,7 +19,15 @@
 
 namespace frc2 {
 
-class TestSubsystem : public SubsystemBase {};
+class TestSubsystem : public SubsystemBase {
+ public:
+  explicit TestSubsystem(std::function<void()> periodic = [] {})
+      : m_periodic{periodic} {}
+  void Periodic() override { m_periodic(); }
+
+ private:
+  std::function<void()> m_periodic;
+};
 
 /**
  * NOTE: Moving mock objects causes EXPECT_CALL to not work correctly!
diff --git a/wpilibNewCommands/src/test/native/cpp/frc2/command/SchedulerTest.cpp b/wpilibNewCommands/src/test/native/cpp/frc2/command/SchedulerTest.cpp
index ce02ba0f96..3bade0ab09 100644
--- a/wpilibNewCommands/src/test/native/cpp/frc2/command/SchedulerTest.cpp
+++ b/wpilibNewCommands/src/test/native/cpp/frc2/command/SchedulerTest.cpp
@@ -43,14 +43,30 @@ TEST_F(SchedulerTest, SchedulerLambdaInterrupt) {
   EXPECT_EQ(counter, 1);
 }
 
+TEST_F(SchedulerTest, RegisterSubsystem) {
+  CommandScheduler scheduler = GetScheduler();
+
+  int counter = 0;
+  TestSubsystem system{[&counter] { counter++; }};
+
+  EXPECT_NO_FATAL_FAILURE(scheduler.RegisterSubsystem(&system));
+
+  scheduler.Run();
+  EXPECT_EQ(counter, 1);
+}
+
 TEST_F(SchedulerTest, UnregisterSubsystem) {
   CommandScheduler scheduler = GetScheduler();
 
-  TestSubsystem system;
+  int counter = 0;
+  TestSubsystem system{[&counter] { counter++; }};
 
   scheduler.RegisterSubsystem(&system);
 
   EXPECT_NO_FATAL_FAILURE(scheduler.UnregisterSubsystem(&system));
+
+  scheduler.Run();
+  ASSERT_EQ(counter, 0);
 }
 
 TEST_F(SchedulerTest, SchedulerCancelAll) {