diff --git a/Qwirkle/QwirkleClassLibrary/Score.cs b/Qwirkle/QwirkleClassLibrary/Score.cs
index db38754..ff52f78 100644
--- a/Qwirkle/QwirkleClassLibrary/Score.cs
+++ b/Qwirkle/QwirkleClassLibrary/Score.cs
@@ -15,7 +15,7 @@ namespace QwirkleClassLibrary
         {
             if (p == null)
             {
-                throw new NullReferenceException("player");
+                throw new ArgumentNullException(nameof(p), "player cannot be null");
             }
             else
             {   PlayerScore = 0;
diff --git a/Qwirkle/TestBase/TestBoard.cs b/Qwirkle/TestBase/TestBoard.cs
index f56f181..2ad505c 100644
--- a/Qwirkle/TestBase/TestBoard.cs
+++ b/Qwirkle/TestBase/TestBoard.cs
@@ -62,7 +62,7 @@ public class TestBoard
     {
         Board board = new Board(12, 12);
 
-        Assert.Equal((12 * 12), board.GetCells().Count());
+        Assert.Equal((12 * 12), board.GetCells().Count);
     }
 
     [Fact]
@@ -82,7 +82,7 @@ public class TestBoard
         }
         ReadOnlyCollection<Cell> readCells = cells.AsReadOnly();
 
-        Assert.Equal(readCells.Count(), board.GetReadCells().Count());
+        Assert.Equal(readCells.Count, board.GetReadCells().Count);
     }
 
 
diff --git a/Qwirkle/TestBase/TestScore.cs b/Qwirkle/TestBase/TestScore.cs
index 0b98fc5..ea8efd2 100644
--- a/Qwirkle/TestBase/TestScore.cs
+++ b/Qwirkle/TestBase/TestScore.cs
@@ -8,11 +8,12 @@ public class TestScore
     //[InlineData(true)]
     public void Test_CellScoreConstructor(bool except)
     {
-        /*if (!except)
+        if (!except)
         {
             Assert.Throws<ArgumentNullException>(() => new Score(null));
             return;
-        }*/
+        }
+        
         Player? p = new Player("test");
         Score score = new Score(p);
         Assert.True(true);