diff --git a/labs/trees_I/README.md b/labs/trees_I/README.md
index e562842..fff7a45 100644
--- a/labs/trees_I/README.md
+++ b/labs/trees_I/README.md
@@ -4,11 +4,19 @@
 
 *estimate: 20-30 minutes*
 
+Pair up with one other student in your lab section and complete the exercises below. Please raise your hand and ask for help from a TA or mentor if you get stuck or are uncertain about any of the terms used below.
+
 problem 1: Draw a binary tree with 4 levels with the integers 1-7 such that the sum of elements on every level of the tree is the same.
 
 problem 2: Create a exactly balanced binary search tree with 7 color words (order the colors alphabetically).
 
-problem 3: Draw a exactly-balanced binary search tree containing the letters of the word: uncopyrightable
+problem 3: Arrange the following items of clothing in a tree with 3 levels such that the parent of every node is generally donned before the child when dressing in the morning: jacket, pants, shoes, shirt, undergarments, socks, and belt.
+
+problem 4: Draw a binary search tree with the integers 1-7, where 3 has no parent and 5 has no children, and there are no other elements at the same level as 5.
+
+problem 5: What is the sum of the leaf nodes in a perfectly balanced binary search tree containing the powers of 2 less than 128?
+
+problem 6: Draw a exactly-balanced binary search tree containing the letters of the word: uncopyrightable
 
  
  
@@ -20,7 +28,7 @@ problem 3: Draw a exactly-balanced binary search tree containing the letters of
 
 What is the pre-order traversal of the tree above?
 
-problem 4: Now draw a exactly-balanced binary tree of characters such that a post-order traversal spells the word: uncopyrightable
+problem 7: Now draw a exactly-balanced binary tree of characters such that a post-order traversal spells the word: uncopyrightable