diff --git a/.classpath b/.classpath
new file mode 100644
index 0000000..3e0fb27
--- /dev/null
+++ b/.classpath
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>
diff --git a/src/debug/ContainerArray.java b/src/debug/ContainerArray.java
index 124ece6..679bd2e 100755
--- a/src/debug/ContainerArray.java
+++ b/src/debug/ContainerArray.java
@@ -1,33 +1,48 @@
 package debug;
 
+import java.util.ArrayList;
+import java.util.List;
+
 
 public class ContainerArray<E> {
-    private int initialCapacity = 10;
-    private int currentSize = 0;
-    private Object[] internalArray;
+    private int limit;
+    private List<E> internalArray;
 
     public ContainerArray () {
         this(10);
     }
 
-    public ContainerArray (int initialCapacity) {
-        internalArray = new Object[initialCapacity];
+    public ContainerArray (int limit) {
+        internalArray = new ArrayList<>();
+        this.limit = limit;
     }
 
     public void add (E element) {
-        internalArray[currentSize++] = element;
+    	if (size() < limit){
+         internalArray.add(element);
+    	}
     }
 
     public int size () {
-        return currentSize;
+        return internalArray.size();
     }
 
     public void remove (E objectToRemove) {
-        currentSize--;
+			if (internalArray.contains(objectToRemove)){
+				internalArray.remove(objectToRemove);
+			}
     }
 
-    @SuppressWarnings("unchecked")
     public E get (int index) {
-        return (E)internalArray[index];
+        return internalArray.get(index);
     }
+
+	public boolean contains(E element) {
+		for (int i = 0; i < internalArray.size(); i++ ){
+			if (internalArray.get(i).equals(element)){
+				return true;
+			}
+		}
+		return false;
+	}
 }
diff --git a/src/debug/ContainerArrayTest.java b/src/debug/ContainerArrayTest.java
index c566d50..fd7f175 100755
--- a/src/debug/ContainerArrayTest.java
+++ b/src/debug/ContainerArrayTest.java
@@ -12,6 +12,15 @@ public class ContainerArrayTest {
     public void setUp () {
         myContainer = new ContainerArray<>();
     }
+    
+    @Test 
+    public void testAddPastLimit (){
+    	for(int i=0; i<10;i++) {
+    		myContainer.add("Eagle");
+    	}
+        myContainer.add("Hawk");
+        assertFalse(myContainer.contains("Hawk"));
+    }
 
     @Test
     public void testSizeChangeWithAdd () {
@@ -25,7 +34,7 @@ public void testSizeChangeWithAdd () {
     public void testObjectIsStored () {
         String alligator = "Alligator";
         myContainer.add(alligator);
-        assertEquals("Add should be same reference", alligator, myContainer.get(0));
+        assertTrue(myContainer.contains(alligator));
     }
 
     @Test
@@ -42,6 +51,7 @@ public void testObjectIsRemoved () {
         myContainer.add("Alligator");
         myContainer.add("Bear");
         myContainer.remove("Bear");
-        assertEquals("Remove should be same reference", alligator, myContainer.get(0));
+        assertFalse(myContainer.contains("Bear"));
     }
+        
 }
diff --git a/src/tdd/Sheet.java b/src/tdd/Sheet.java
new file mode 100644
index 0000000..f6beef8
--- /dev/null
+++ b/src/tdd/Sheet.java
@@ -0,0 +1,53 @@
+package tdd;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class Sheet {
+
+	private Map<String, String> myMap;
+	
+	public Sheet() {
+		myMap = new HashMap<>();
+	}
+	
+	public String get(String string) {
+		if(myMap.containsKey(string)) {
+			if(isNumeric(myMap.get(string))) {
+				return myMap.get(string).trim();
+			}
+			else {
+				return myMap.get(string);
+			}
+		}
+		else {
+			return "";
+		}
+	}
+
+	public void put(String theCell, String string) {
+		myMap.put(theCell, string);
+	}
+
+	private static boolean isNumeric(String str)  
+	{  
+		try  
+		{  
+			double d = Double.parseDouble(str);  
+		}  
+		catch(NumberFormatException nfe)  
+		{  
+			return false;  
+		}  
+		return true;  
+	}
+
+	public String getLiteral(String theCell) {
+		if(myMap.containsKey(theCell)) {
+			return myMap.get(theCell);
+		}
+		else {
+			return "";
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/tdd/TestSheet.java b/src/tdd/TestSheet.java
new file mode 100644
index 0000000..cb41723
--- /dev/null
+++ b/src/tdd/TestSheet.java
@@ -0,0 +1,83 @@
+package tdd;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+public class TestSheet {
+
+	@Test
+	public void testThatCellsAreEmptyByDefault() {
+	  Sheet sheet = new Sheet();
+	  assertEquals("", sheet.get("A1"));
+	  assertEquals("", sheet.get("ZX347"));
+	}
+	
+	@Test
+	public void testThatTextCellsAreStored() {
+	  Sheet sheet = new Sheet();
+	  String theCell = "A21";
+
+	  sheet.put(theCell, "A string");
+	  assertEquals("A string", sheet.get(theCell));
+
+	  sheet.put(theCell, "A different string");
+	  assertEquals("A different string", sheet.get(theCell));
+
+	  sheet.put(theCell, "");
+	  assertEquals("", sheet.get(theCell));
+	}
+	
+	@Test
+	public void testThatManyCellsExist() {
+	  Sheet sheet = new Sheet();
+	  sheet.put("A1", "First");
+	  sheet.put("X27", "Second");
+	  sheet.put("ZX901", "Third");
+	
+	  assertEquals("A1", "First", sheet.get("A1"));
+	  assertEquals("X27", "Second", sheet.get("X27"));
+	  assertEquals("ZX901", "Third", sheet.get("ZX901"));
+	
+	  sheet.put("A1", "Fourth");
+	  assertEquals("A1 after", "Fourth", sheet.get("A1"));
+	  assertEquals("X27 same", "Second", sheet.get("X27"));
+	  assertEquals("ZX901 same", "Third", sheet.get("ZX901"));
+	}
+	
+	@Test
+	public void testThatNumericCellsAreIdentifiedAndStored() {
+	  Sheet sheet = new Sheet();
+	  String theCell = "A21";
+
+	  sheet.put(theCell, "X99"); // "Obvious" string
+	  assertEquals("X99", sheet.get(theCell));
+
+	  sheet.put(theCell, "14"); // "Obvious" number
+	  assertEquals("14", sheet.get(theCell));
+
+	  sheet.put(theCell, " 99 X"); // Whole string must be numeric
+	  assertEquals(" 99 X", sheet.get(theCell));
+
+	  sheet.put(theCell, " 1234 "); // Blanks ignored
+	  assertEquals("1234", sheet.get(theCell));
+
+	  sheet.put(theCell, " "); // Just a blank
+	  assertEquals(" ", sheet.get(theCell));
+	}
+	
+	@Test
+	public void testThatWeHaveAccessToCellLiteralValuesForEditing() { 
+		  Sheet sheet = new Sheet();
+		  String theCell = "A21";
+
+		  sheet.put(theCell, "Some string"); 
+		  assertEquals("Some string", sheet.getLiteral(theCell));
+
+		  sheet.put(theCell, " 1234 "); 
+		  assertEquals(" 1234 ", sheet.getLiteral(theCell));
+
+		  sheet.put(theCell, "=7"); // Foreshadowing formulas:)
+		  assertEquals("=7", sheet.getLiteral(theCell));
+		}
+}