diff --git a/test/propeller/tools/character_test.cljc b/test/propeller/tools/character_test.cljc
index 2b32d9f..cf23fa8 100644
--- a/test/propeller/tools/character_test.cljc
+++ b/test/propeller/tools/character_test.cljc
@@ -5,9 +5,7 @@
   (t/is (= 97 (c/get-ascii (first "abc")))))
 
 (t/deftest is-letter-test
-  (t/is  (c/is-letter (first "abc")))
-  ;(t/is (= false (c/is-letter 97)))
-  )
+  (t/is  (c/is-letter (first "abc"))))
 
 (t/deftest is-digit-test
   (t/is (c/is-digit (first "545")))
diff --git a/test/propeller/tools/math_test.cljc b/test/propeller/tools/math_test.cljc
index 4f35ebb..c189536 100644
--- a/test/propeller/tools/math_test.cljc
+++ b/test/propeller/tools/math_test.cljc
@@ -20,5 +20,44 @@
   (t/is (= 1.0 (m/cos 0)))
   (t/is (= -1.0 (m/cos (* 3 m/PI)))))
 
-(t/deftest div
-  (t/is ))
+(t/deftest div-test
+  (t/is (= 0.1 (m/div 1 10))))
+
+(t/deftest exp-test
+  (t/is (m/approx= (m/exp 2) 7.3890 0.001)))
+
+(t/deftest floor-test
+  (t/is (= 4.0 (m/floor 4.9)))
+  (t/is (= 4.0 (m/floor 4.5)))
+  (t/is (= -11.0 (m/floor -10.5))))
+
+(t/deftest log-test
+  (t/is (= (m/log (m/exp 1)) 1.0))
+  (t/is (= (m/log 10 10) 1.0)))
+
+(t/deftest pow-test
+  (t/is (= (m/pow 5 2) 25.0)))
+
+(t/deftest root
+  (t/is (= (m/root 16 2) 4.0)))
+
+(t/deftest sign-test
+  (t/is (= -1 (m/sign -10)))
+  (t/is (= 1 (m/sign 10)))
+  (t/is (= 0 (m/sign 0))))
+
+(t/deftest sin-test
+   (t/is (= 1.0 (m/sin (/ m/PI 2))))
+   (t/is (m/approx= 0 (m/sin  m/PI) 0.0001)))
+
+(t/deftest sqrt-test
+  (t/is (= (m/sqrt 4) 2.0)))
+
+(t/deftest square-test
+  (t/is (= (m/square 5) 25)))
+
+(t/deftest tan-test
+      (t/is (m/approx= (m/tan (/  m/PI 4)) 1.0 0.00001))
+      (t/is (= (m/tan 0) 0.0)))
+
+