diff --git a/lecture/src/main/java/w04/classes/ClassVariable.java b/lecture/src/main/java/w04/classes/ClassVariable.java
new file mode 100644
index 0000000..db1d932
--- /dev/null
+++ b/lecture/src/main/java/w04/classes/ClassVariable.java
@@ -0,0 +1,15 @@
+package w04.classes;
+
+/**
+ * User: Marcin Matuszak
+ * Date: 27.11.12
+ */
+public class ClassVariable {
+
+    public static int counter;
+
+
+    public ClassVariable() {
+        counter++;
+    }
+}
diff --git a/lecture/src/main/java/w04/classes/InstanceVariable.java b/lecture/src/main/java/w04/classes/InstanceVariable.java
new file mode 100644
index 0000000..e77b79d
--- /dev/null
+++ b/lecture/src/main/java/w04/classes/InstanceVariable.java
@@ -0,0 +1,14 @@
+package w04.classes;
+
+/**
+ * User: Marcin Matuszak
+ * Date: 27.11.12
+ */
+public class InstanceVariable {
+
+    public int counter;
+
+    public InstanceVariable() {
+        counter++;
+    }
+}
diff --git a/lecture/src/test/java/w04/classes/ClassVariableTest.java b/lecture/src/test/java/w04/classes/ClassVariableTest.java
new file mode 100644
index 0000000..ffb85de
--- /dev/null
+++ b/lecture/src/test/java/w04/classes/ClassVariableTest.java
@@ -0,0 +1,16 @@
+package w04.classes;
+
+import org.testng.annotations.Test;
+
+/**
+ * User: Marcin Matuszak
+ * Date: 27.11.12
+ */
+public class ClassVariableTest {
+
+    @Test
+    public void test_number_of_instances() {
+
+
+    }
+}
diff --git a/lecture/src/test/java/w04/classes/InstanceVariableTest.java b/lecture/src/test/java/w04/classes/InstanceVariableTest.java
new file mode 100644
index 0000000..decd271
--- /dev/null
+++ b/lecture/src/test/java/w04/classes/InstanceVariableTest.java
@@ -0,0 +1,18 @@
+package w04.classes;
+
+import org.testng.annotations.Test;
+
+import static org.testng.Assert.assertEquals;
+
+/**
+ * User: Marcin Matuszak
+ * Date: 27.11.12
+ */
+public class InstanceVariableTest {
+
+    @Test
+    public void test_number_of_instances() {
+    }
+
+
+}
diff --git a/w01-worm-up/.gitignore b/w01-worm-up/.gitignore
index d9bf2eb..3548752 100644
--- a/w01-worm-up/.gitignore
+++ b/w01-worm-up/.gitignore
@@ -1,7 +1,7 @@
 .idea
 atlassian-ide-plugin.xml
 *.iml
-classes
+java.classes
 .gradle
 cache/
 datatypes/build/