diff --git a/.devcontainer.json b/.devcontainer.json
new file mode 100644
index 0000000..bfbeb0d
--- /dev/null
+++ b/.devcontainer.json
@@ -0,0 +1,3 @@
+{
+    "image": "mcr.microsoft.com/devcontainers/java:21"
+}
\ No newline at end of file
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
new file mode 100644
index 0000000..add4f4e
--- /dev/null
+++ b/.vscode/extensions.json
@@ -0,0 +1,5 @@
+{
+    "recommendations": [
+        "vscjava.vscode-java-pack"
+    ]
+}
\ No newline at end of file
diff --git a/Exercise.java b/Exercise.java
index a8fab57..13d4bb5 100644
--- a/Exercise.java
+++ b/Exercise.java
@@ -7,13 +7,13 @@ public static void main(String[] args) {
     FilteredStudents adultStudents = new FilteredStudents((student) -> student.age > 18);
     adultStudents.add(steffen);
     adultStudents.add(kid);
-    adultStudents.printStudents();
+    adultStudents.forEach(student -> System.out.println(student.name.toUpperCase()));
 
     System.out.println("-----------------------");
 
     FilteredStudents teenStudents = new FilteredStudents(student -> student.age < 18);
     teenStudents.add(steffen);
     teenStudents.add(kid);
-    teenStudents.printStudents();
+    teenStudents.forEach(student -> System.out.println(student.name.toLowerCase()));
   }
 }
diff --git a/FilteredStudents.java b/FilteredStudents.java
index f83d166..a3c10fc 100644
--- a/FilteredStudents.java
+++ b/FilteredStudents.java
@@ -1,4 +1,5 @@
 import java.util.ArrayList;
+import java.util.function.Consumer;
 import java.util.function.Predicate;
 
 public class FilteredStudents {
@@ -16,7 +17,9 @@ public void add(Student element) {
     }
   }
 
-  public void printStudents() {
-    this.students.forEach((student) -> System.out.println(student));
+  public void forEach(Consumer<Student> consumer) {
+    for (Student student : students) {
+      consumer.accept(student);
+    }
   }
 }