diff --git a/core/src/test/java/edu/umd/cs/piccolo/PRootTest.java b/core/src/test/java/edu/umd/cs/piccolo/PRootTest.java
new file mode 100644
index 0000000..f3acd36
--- /dev/null
+++ b/core/src/test/java/edu/umd/cs/piccolo/PRootTest.java
@@ -0,0 +1,155 @@
+package edu.umd.cs.piccolo;
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+import javax.swing.Timer;
+
+import junit.framework.TestCase;
+import edu.umd.cs.piccolo.activities.PActivity;
+
+public class PRootTest extends TestCase {    
+    private PRoot root;
+    private MockPropertyChangeListener mockListener;
+
+    public void setUp() {
+        root = new PRoot();
+        mockListener = new MockPropertyChangeListener();
+    }
+
+    public void testActivityScheduleIsNotNullByDefault() {
+        assertNotNull(root.getActivityScheduler());
+    }
+
+    public void testGetRootReturnsItself() {
+        assertSame(root, root.getRoot());
+    }
+
+    public void testGetDefaultInputManagerIsNotNullByDefault() {
+        assertNotNull(root.getDefaultInputManager());
+    }
+
+    public void testAddInputSourceFirePropertyChangeEvent() {
+        root.addPropertyChangeListener(PRoot.PROPERTY_INPUT_SOURCES, mockListener);
+
+        PRoot.InputSource newSource = new PRoot.InputSource() {
+            public void processInput() {
+
+            }
+        };
+        root.addInputSource(newSource);
+
+        assertEquals(1, mockListener.getPropertyChangeCount());
+    }
+
+    public void testCreateTimerReturnsATimer() {
+        Timer timer = root.createTimer(1, new ActionListener() {
+            public void actionPerformed(ActionEvent arg0) {
+            }
+        });
+        assertNotNull(timer);
+    }
+
+    public void testCreateTimerReturnsATimerWhenDelayIs0() {
+        Timer timer = root.createTimer(0, new ActionListener() {
+            public void actionPerformed(ActionEvent arg0) {
+            }
+        });
+        assertNotNull(timer);
+    }
+
+    public void testRemoveInputSourceDoesNothingIfStranger() {
+        PRoot.InputSource strangeSource = new PRoot.InputSource() {
+            public void processInput() {
+
+            }
+        };
+
+        root.removeInputSource(strangeSource);
+    }
+
+    public void testGlobalTimeIsNotZeroBeforeCallToProcessInputs() {
+        assertFalse(0 == root.getGlobalTime());
+    }
+
+    public void testProcessInputDelegatesToInputSources() {        
+        MockInputSource newSource = new MockInputSource();
+        root.addInputSource(newSource);
+        root.processInputs();
+        assertEquals(1, newSource.getProcessInputCalls());
+    }
+    
+    public void testProcessInputProcessesActivities() {
+        MockPActivity activity = new MockPActivity(100);
+        root.addActivity(activity);
+        root.processInputs();
+        assertTrue(activity.isActivityStarted());
+        
+    }   
+    
+    public void testSetFullBoundsInvalidPerists() {
+        root.setFullBoundsInvalid(true);
+        assertTrue(root.getFullBoundsInvalid());
+    }
+    
+    public void testSetChildBoundsInvalidPerists() {
+        root.setChildBoundsInvalid(true);
+        assertTrue(root.getChildBoundsInvalid());
+    }
+    
+    public void testSetPaintInvalidPersists() {
+        root.setPaintInvalid(true);
+        assertTrue(root.getPaintInvalid());
+    }
+    
+    public void testSetChildPaintInvalidPersists() {
+        root.setChildPaintInvalid(true);
+        assertTrue(root.getChildPaintInvalid());
+    }
+    
+    public void testWaitForActivitiesDoesSo() {
+        MockPActivity activity = new MockPActivity(1);
+        root.addActivity(activity);
+        root.waitForActivities();
+        assertTrue(activity.isActivityFished());
+    }
+
+    private final class MockInputSource implements PRoot.InputSource {
+        private int processInputCalls;
+
+        public int getProcessInputCalls() {
+            return processInputCalls;
+        }
+        
+        public void processInput() {
+            processInputCalls ++;
+        }
+    }
+    
+    private final class MockPActivity extends PActivity {
+        private boolean activityStarted;
+        private boolean activityFinished;
+
+        private MockPActivity(long aDuration) {
+            super(aDuration);
+        }
+
+        public boolean isActivityFished() {
+            return activityFinished;
+        }
+
+        public boolean isActivityStarted() {
+            return activityStarted;
+        }
+
+        protected void activityStarted() {
+            this.activityStarted = true;
+            super.activityStarted();
+        }
+        
+        protected void activityFinished() {
+            this.activityFinished = true;
+            super.activityFinished();
+        }
+    }
+}