diff --git a/labs/06_lists_iterators/checkpoint1.cpp b/labs/06_lists_iterators/checkpoint1.cpp
new file mode 100644
index 0000000..e7b9ea4
--- /dev/null
+++ b/labs/06_lists_iterators/checkpoint1.cpp
@@ -0,0 +1,47 @@
+#include <iostream>
+#include <string>
+#include <vector>
+
+
+template <class T>
+void print(std::vector<T> &data, const std::string &label) {
+  std::cout << label << " ";
+  for (int i = 0; i < data.size(); i++) {
+    std::cout << " " << data[i];
+  }
+  std::cout << std::endl;
+}
+
+
+template <class T>
+void reverse(std::vector<T> &data) {
+
+  // FILL IN THIS FUNCTION
+  
+}
+
+
+int main() {
+  std::vector<int> data;
+  data.push_back(1);
+  data.push_back(2);
+  data.push_back(3);
+  data.push_back(4);
+  data.push_back(5);
+  data.push_back(6);
+  data.push_back(7);
+
+  print(data,"before:");
+  reverse(data);
+  print(data,"after: ");
+
+  std::vector<std::string> data2;
+  data2.push_back("apple");
+  data2.push_back("banana");
+  data2.push_back("carrot");
+  data2.push_back("date");
+
+  print(data2,"before:");
+  reverse(data2);
+  print(data2,"after: ");
+}
diff --git a/labs/06_lists_iterators/checkpoint3.cpp b/labs/06_lists_iterators/checkpoint3.cpp
new file mode 100644
index 0000000..d0d12b7
--- /dev/null
+++ b/labs/06_lists_iterators/checkpoint3.cpp
@@ -0,0 +1,64 @@
+#include <iostream>
+#include <string>
+
+
+// Note: It's ok that all the member variables are public for this
+// tiny class.  We'll build up to a more robust and complete linked
+// list implementation in lecture 11.
+template <class T>
+class Node {
+public:
+  T value;
+  Node<T> *ptr;
+};
+
+
+
+template <class T>
+void print(Node<T> *data, const std::string &label) {
+  std::cout << label;
+  Node<T> *tmp = data;
+  while (tmp != NULL) {
+    std::cout << " " << tmp->value;
+    tmp = tmp->ptr;
+  }
+  std::cout << std::endl;
+}
+
+
+
+template <class T>
+void reverse(Node<T>* &input) {
+
+  // FILL IN THIS FUNCTION
+
+}
+
+
+
+
+int main() {
+
+  // manually create a linked list of notes with 4 elements
+  Node<int>* my_list = new Node<int>; 
+  my_list->value = 1; 
+  my_list->ptr = new Node<int>;
+  my_list->ptr->value = 2;
+  my_list->ptr->ptr = new Node<int>;
+  my_list->ptr->ptr->value = 3;
+  my_list->ptr->ptr->ptr = new Node<int>;
+  my_list->ptr->ptr->ptr->value = 4;
+  my_list->ptr->ptr->ptr->ptr = NULL;
+
+  
+  print(my_list,"my_list before");
+  reverse(my_list);
+  print(my_list,"my_list after ");
+
+
+  // Note: We are not deleting any of the Nodes we created...  so this
+  // program has memory leaks!  More on this in lecture 11.
+
+}
+
+// ===========================================================================