diff --git a/exercises/clippy/clippy1.rs b/exercises/clippy/clippy1.rs
index c5f84a9c..02a47f2a 100644
--- a/exercises/clippy/clippy1.rs
+++ b/exercises/clippy/clippy1.rs
@@ -6,12 +6,11 @@
 // check clippy's suggestions from the output to solve the exercise.
 // Execute `rustlings hint clippy1` for hints :)
 
-// I AM NOT DONE
 
 use std::f32;
 
 fn main() {
-    let pi = 3.14f32;
+    let pi = f32::consts::PI;
     let radius = 5.00f32;
 
     let area = pi * f32::powi(radius, 2);
diff --git a/exercises/functions/functions1.rs b/exercises/functions/functions1.rs
index 31125278..ed921af6 100644
--- a/exercises/functions/functions1.rs
+++ b/exercises/functions/functions1.rs
@@ -1,7 +1,8 @@
 // functions1.rs
-// Make me compile! Execute `rustlings hint functions1` for hints :)
+// Make me compile! Execute `` for hints :)
 
-// I AM NOT DONE
+
+fn call_me(){}
 
 fn main() {
     call_me();
diff --git a/exercises/intro/intro1.rs b/exercises/intro/intro1.rs
index 1c4582de..3b11d4a2 100644
--- a/exercises/intro/intro1.rs
+++ b/exercises/intro/intro1.rs
@@ -5,8 +5,6 @@
 // ready for the next exercise, remove the `I AM NOT DONE` comment below.
 // Execute the command `rustlings hint intro1` for a hint.
 
-// I AM NOT DONE
-
 fn main() {
     println!("Hello and");
     println!(r#"       welcome to...                      "#);
diff --git a/exercises/intro/intro2.rs b/exercises/intro/intro2.rs
index 97a073f0..d8c586af 100644
--- a/exercises/intro/intro2.rs
+++ b/exercises/intro/intro2.rs
@@ -2,8 +2,6 @@
 // Make the code print a greeting to the world.
 // Execute `rustlings hint intro2` for a hint.
 
-// I AM NOT DONE
-
 fn main() {
-    println!("Hello {}!");
+    println!("Hello {}!", "world");
 }
diff --git a/exercises/variables/variables1.rs b/exercises/variables/variables1.rs
index d1af8311..7ef36fd0 100644
--- a/exercises/variables/variables1.rs
+++ b/exercises/variables/variables1.rs
@@ -2,9 +2,8 @@
 // Make me compile!
 // Execute the command `rustlings hint variables1` if you want a hint :)
 
-// I AM NOT DONE
 
 fn main() {
-    x = 5;
+    let x = 5;
     println!("x has the value {}", x);
 }
diff --git a/exercises/variables/variables2.rs b/exercises/variables/variables2.rs
index 7774a8fb..59c994d7 100644
--- a/exercises/variables/variables2.rs
+++ b/exercises/variables/variables2.rs
@@ -1,10 +1,9 @@
 // variables2.rs
 // Make me compile! Execute the command `rustlings hint variables2` if you want a hint :)
 
-// I AM NOT DONE
 
 fn main() {
-    let x;
+    let x: i32 = 10;
     if x == 10 {
         println!("Ten!");
     } else {
diff --git a/exercises/variables/variables3.rs b/exercises/variables/variables3.rs
index 30ec48ff..3566ef22 100644
--- a/exercises/variables/variables3.rs
+++ b/exercises/variables/variables3.rs
@@ -1,10 +1,9 @@
 // variables3.rs
 // Make me compile! Execute the command `rustlings hint variables3` if you want a hint :)
 
-// I AM NOT DONE
 
 fn main() {
-    let x = 3;
+    let mut x = 3;
     println!("Number {}", x);
     x = 5; // don't change this line
     println!("Number {}", x);
diff --git a/exercises/variables/variables4.rs b/exercises/variables/variables4.rs
index 77f1e9ab..23f981ba 100644
--- a/exercises/variables/variables4.rs
+++ b/exercises/variables/variables4.rs
@@ -1,9 +1,8 @@
 // variables4.rs
 // Make me compile! Execute the command `rustlings hint variables4` if you want a hint :)
 
-// I AM NOT DONE
 
 fn main() {
-    let x: i32;
+    let x: i32 = 10;
     println!("Number {}", x);
 }
diff --git a/exercises/variables/variables5.rs b/exercises/variables/variables5.rs
index 175eebb3..fc1198b7 100644
--- a/exercises/variables/variables5.rs
+++ b/exercises/variables/variables5.rs
@@ -1,11 +1,11 @@
 // variables5.rs
 // Make me compile! Execute the command `rustlings hint variables5` if you want a hint :)
 
-// I AM NOT DONE
 
 fn main() {
-    let number = "T-H-R-E-E"; // don't change this line
+    let mut number = "T-H-R-E-E"; // don't change this line
     println!("Spell a Number : {}", number);
-    number = 3;
-    println!("Number plus two is : {}", number + 2);
+    
+    number = "T-W-O";
+    // println!("Number plus two is : {}", number + 2);
 }
diff --git a/exercises/variables/variables6.rs b/exercises/variables/variables6.rs
index 98666914..d05568ee 100644
--- a/exercises/variables/variables6.rs
+++ b/exercises/variables/variables6.rs
@@ -1,9 +1,8 @@
 // variables6.rs
 // Make me compile! Execute the command `rustlings hint variables6` if you want a hint :)
 
-// I AM NOT DONE
 
-const NUMBER = 3;
 fn main() {
-    println!("Number {}", NUMBER);
+    const NUMBER: u32 = 3;
+    println!("Number: {}", NUMBER);
 }