diff --git a/school_project/test/models/cpu/utils/test_model.py b/school_project/test/models/cpu/utils/test_model.py
index e69de29..f0d2156 100644
--- a/school_project/test/models/cpu/utils/test_model.py
+++ b/school_project/test/models/cpu/utils/test_model.py
@@ -0,0 +1,119 @@
+import unittest
+
+# Test XOR implementation of Model for its lesser computation time
+from school_project.models.cpu.xor import XORModel
+
+class TestModel(unittest.TestCase):
+    """Unit tests for model module."""
+    def __init__(self, *args, **kwargs) -> None:
+        """Initialise unit tests and inputs."""
+        super(TestModel, self).__init__(*args, **kwargs)
+
+    def test_train_dataset_size(self) -> None:
+        """Test the size of training dataset to be value chosen."""
+        train_dataset_size = 4
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = train_dataset_size,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        self.assertEqual(first=model.layers.head.input.shape[1],
+                         second=train_dataset_size)
+
+    def test_network_shape(self) -> None:
+        """Test the neuron count of each layer to match the set shape of the 
+           network."""
+        layers_shape = [2, 100, 100, 1]
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.input_neuron_count,
+                             second=layers_shape[count])
+
+    def test_learning_rates(self) -> None:
+        """Test learning rate of each layer to be the same."""
+        learning_rate = 0.1
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = learning_rate,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.learning_rate, second=learning_rate)
+
+    def test_relu_model_transfer_types(self) -> None:
+        """Test transfer type of each layer to match whats set."""
+        transfer_types = ['relu', 'relu', 'sigmoid']
+        model = XORModel(hidden_layers_shape = [100, 100],
+                              train_dataset_size = 4,
+                              learning_rate = 0.1,
+                              use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.transfer_type,
+                             second=transfer_types[count])
+
+    def test_sigmoid_model_transfer_types(self) -> None:
+        """Test transfer type of each layer to match whats set."""
+        transfer_types = ['sigmoid', 'sigmoid', 'sigmoid']
+        model = XORModel(hidden_layers_shape = [100, 100],
+                                 train_dataset_size = 4,
+                                 learning_rate = 0.1,
+                                 use_relu = False)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.transfer_type,
+                             second=transfer_types[count])
+
+    def test_weight_matrice_shapes(self) -> None:
+        """Test that each layer's weight matrix has the same number of columns 
+        as the layer's input matrix's number of rows, for the matrice 
+        multiplication."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.weights.shape[1],
+                             second=layer.input.shape[0])
+
+    def test_bias_matrice_shapes(self) -> None:
+        """Test that each layer's bias matrix has the same number of rows 
+        as the result of the layer's weights and input multiplication, for 
+        element-wise addition of the biases."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.biases.shape[0],
+                             second=layer.weights.shape[0])
+
+    def test_layer_output_shapes(self) -> None:
+        """Test the shape of each layer's activation function's output."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(
+                         first=(layer.weights.shape[0], layer.input.shape[1]),
+                         second=layer.output.shape
+                         )
+
+if __name__ == '__main__':
+    unittest.main()
\ No newline at end of file
diff --git a/school_project/test/models/cpu/utils/test_tools.py b/school_project/test/models/cpu/utils/test_tools.py
index 1603d6f..e982063 100644
--- a/school_project/test/models/cpu/utils/test_tools.py
+++ b/school_project/test/models/cpu/utils/test_tools.py
@@ -1,37 +1,26 @@
 import unittest
+
 from school_project.models.cpu.utils import tools
 
 class TestTools(unittest.TestCase):
-    def __init__(self, *args, **kwargs):
+    """Unit tests for the tools module."""
+    def __init__(self, *args, **kwargs) -> None:
+        """Initialise unit tests."""
         super(TestTools, self).__init__(*args, **kwargs)
 
-    def test_sigmoid(self) -> None:
-        """Test sigmoid output range to be within 0-1.
-        
-        Raises:
-            AssertionError: if sigmoid output range is not within 0-1.
-        
-        """
-        test_inputs = [-100,0,100]
-        for test_input in test_inputs:
-            output = tools.sigmoid(test_input)
-            self.assertTrue(output >= 0 and output <= 1,
-                            "Sigmoid should return a number between 0 and 1")
-            
     def test_relu(self) -> None:
-        """Test ReLu output range to be >=0.
-        
-        Raises:
-            AssertionError: if relu output range is not >=0.
-        
-        """
-        test_inputs = [-100,0,100]
+        """Test ReLu output range to be >=0."""
+        test_inputs = [-100, 0, 100]
+        for test_input in test_inputs:
+            output = tools.relu(z=test_input)
+            self.assertGreaterEqual(a=output, b=0)
+
+    def test_sigmoid(self) -> None:
+        """Test sigmoid output range to be within 0-1."""
+        test_inputs = [-100, 0, 100]
         for test_input in test_inputs:
-            output = tools.relu(test_input)
-            self.assertTrue(
-                      output >= 0,
-                      "ReLu should return a number greater than or equal to 0"
-                      )
+            output = tools.sigmoid(z=test_input)
+            self.assertTrue(expr=output >= 0 and output <= 1)
 
 if __name__ == '__main__':
     unittest.main()
\ No newline at end of file
diff --git a/school_project/test/models/gpu/utils/test_model.py b/school_project/test/models/gpu/utils/test_model.py
index e69de29..688364b 100644
--- a/school_project/test/models/gpu/utils/test_model.py
+++ b/school_project/test/models/gpu/utils/test_model.py
@@ -0,0 +1,119 @@
+import unittest
+
+
+# Test XOR implementation of Model for its lesser computation time
+from school_project.models.gpu.xor import XORModel
+
+class TestModel(unittest.TestCase):
+    """Unit tests for model module."""
+    def __init__(self, *args, **kwargs) -> None:
+        """Initialise unit tests and inputs."""
+        super(TestModel, self).__init__(*args, **kwargs)
+
+    def test_train_dataset_size(self) -> None:
+        """Test the size of training dataset to be value chosen."""
+        train_dataset_size = 4
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = train_dataset_size,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        self.assertEqual(first=model.layers.head.input.shape[1],
+                         second=train_dataset_size)
+
+    def test_network_shape(self) -> None:
+        """Test the neuron count of each layer to match the set shape of the 
+           network."""
+        layers_shape = [2, 100, 100, 1]
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.input_neuron_count,
+                             second=layers_shape[count])
+
+    def test_learning_rates(self) -> None:
+        """Test learning rate of each layer to be the same."""
+        learning_rate = 0.1
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = learning_rate,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.learning_rate, second=learning_rate)
+
+    def test_relu_model_transfer_types(self) -> None:
+        """Test transfer type of each layer to match whats set."""
+        transfer_types = ['relu', 'relu', 'sigmoid']
+        model = XORModel(hidden_layers_shape = [100, 100],
+                              train_dataset_size = 4,
+                              learning_rate = 0.1,
+                              use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.transfer_type,
+                             second=transfer_types[count])
+
+    def test_sigmoid_model_transfer_types(self) -> None:
+        """Test transfer type of each layer to match whats set."""
+        transfer_types = ['sigmoid', 'sigmoid', 'sigmoid']
+        model = XORModel(hidden_layers_shape = [100, 100],
+                                 train_dataset_size = 4,
+                                 learning_rate = 0.1,
+                                 use_relu = False)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for count, layer in enumerate(model.layers):
+            self.assertEqual(first=layer.transfer_type,
+                             second=transfer_types[count])
+
+    def test_weight_matrice_shapes(self) -> None:
+        """Test that each layer's weight matrix has the same number of columns 
+        as the layer's input matrix's number of rows, for the matrice 
+        multiplication."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.weights.shape[1],
+                             second=layer.input.shape[0])
+
+    def test_bias_matrice_shapes(self) -> None:
+        """Test that each layer's bias matrix has the same number of rows 
+        as the result of the layer's weights and input multiplication, for 
+        element-wise addition of the biases."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(first=layer.biases.shape[0],
+                             second=layer.weights.shape[0])
+
+    def test_layer_output_shapes(self) -> None:
+        """Test the shape of each layer's activation function's output."""
+        model = XORModel(hidden_layers_shape = [100, 100],
+                         train_dataset_size = 4,
+                         learning_rate = 0.1,
+                         use_relu = True)
+        model.create_model_values()
+        model.train(epoch_count=1)
+        for layer in model.layers:
+            self.assertEqual(
+                         first=(layer.weights.shape[0], layer.input.shape[1]),
+                         second=layer.output.shape)
+
+if __name__ == '__main__':
+    unittest.main()
\ No newline at end of file
diff --git a/school_project/test/models/gpu/utils/test_tools.py b/school_project/test/models/gpu/utils/test_tools.py
index c30eb8b..b7ea1a6 100644
--- a/school_project/test/models/gpu/utils/test_tools.py
+++ b/school_project/test/models/gpu/utils/test_tools.py
@@ -1,37 +1,26 @@
 import unittest
+
 from school_project.models.gpu.utils import tools
 
 class TestTools(unittest.TestCase):
-    def __init__(self, *args, **kwargs):
+    """Unit tests for the tools module."""
+    def __init__(self, *args, **kwargs) -> None:
+        """Initialise unit tests and inputs."""
         super(TestTools, self).__init__(*args, **kwargs)
-
-    def test_sigmoid(self) -> None:
-        """Test sigmoid output range to be within 0-1.
-        
-        Raises:
-            AssertionError: if sigmoid output range is not within 0-1.
-        
-        """
-        test_inputs = [-100,0,100]
-        for test_input in test_inputs:
-            output = tools.sigmoid(test_input)
-            self.assertTrue(output >= 0 and output <= 1,
-                            "Sigmoid should return a number between 0 and 1")
             
     def test_relu(self) -> None:
-        """Test ReLu output range to be >=0.
-        
-        Raises:
-            AssertionError: if relu output range is not >=0.
-        
-        """
-        test_inputs = [-100,0,100]
+        """Test ReLu output range to be >=0. """
+        test_inputs = [-100, 0, 100]
+        for test_input in test_inputs:
+            output = tools.relu(z=test_input)
+            self.assertGreaterEqual(a=output, b=0)
+
+    def test_sigmoid(self) -> None:
+        """Test sigmoid output range to be within 0-1."""
+        test_inputs = [-100, 0, 100]
         for test_input in test_inputs:
-            output = tools.relu(test_input)
-            self.assertTrue(
-                      output >= 0,
-                      "ReLu should return a number greater than or equal to 0"
-                      )
+            output = tools.sigmoid(z=test_input)
+            self.assertTrue(expr=output >= 0 and output <= 1)
 
 if __name__ == '__main__':
     unittest.main()
\ No newline at end of file