diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 634bd0a..7158808 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -193,7 +193,7 @@ jobs:
         run: mix ecto.migrate
       - name: Run coverage
         run: |
-          MIX_ENV=test mix coveralls --no-start --trace
+          MIX_ENV=test mix coveralls
     services:
       pg:
         image: postgres:16
diff --git a/apps/core/lib/core.ex b/apps/core/lib/core.ex
index 1c53942..64ae323 100644
--- a/apps/core/lib/core.ex
+++ b/apps/core/lib/core.ex
@@ -2,17 +2,4 @@ defmodule Core do
   @moduledoc """
   Documentation for `Core`.
   """
-
-  @doc """
-  Hello world.
-
-  ## Examples
-
-      iex> Core.hello()
-      :world
-
-  """
-  def hello do
-    :world
-  end
 end
diff --git a/apps/core/lib/core/schema/user.ex b/apps/core/lib/core/schema/user.ex
index e90c691..4ba9878 100644
--- a/apps/core/lib/core/schema/user.ex
+++ b/apps/core/lib/core/schema/user.ex
@@ -34,7 +34,6 @@ defmodule GoEscuelaLms.Core.Schema.User do
     |> cast(attrs, [:full_name, :email, :birth_date, :role, :password_hash])
     |> validate_required([:full_name, :password_hash])
     |> validate_format(:email, ~r/^[^\s]+@[^\s]+$/, message: "must have the @ sign and no spaces")
-    |> validate_length(:email, max: 160)
     |> put_password_hash()
   end
 
diff --git a/apps/core/test/core/schema/course_test.exs b/apps/core/test/core/schema/course_test.exs
index 7b8c012..7b18b9b 100644
--- a/apps/core/test/core/schema/course_test.exs
+++ b/apps/core/test/core/schema/course_test.exs
@@ -1,6 +1,5 @@
 defmodule Core.CourseTest do
   use ExUnit.Case
-  use Core.DataCase
 
   alias GoEscuelaLms.Core.Schema.Course
 
@@ -8,7 +7,7 @@ defmodule Core.CourseTest do
     @valid_attrs %{name: "Course I", description: "lorem ipsum", enabled: true}
     @invalid_attrs %{name: nil, description: nil}
 
-    test "create_course/1 with valid data creates a user" do
+    test "create/1 with valid data creates a course" do
       assert {:ok, %Course{} = course} = Course.create(@valid_attrs)
       assert course.name == "Course I"
       assert course.description == "lorem ipsum"
diff --git a/apps/core/test/core/schema/user_test.exs b/apps/core/test/core/schema/user_test.exs
new file mode 100644
index 0000000..f8e529d
--- /dev/null
+++ b/apps/core/test/core/schema/user_test.exs
@@ -0,0 +1,31 @@
+defmodule Core.UserTest do
+  use ExUnit.Case
+
+  alias GoEscuelaLms.Core.Schema.User
+
+  describe "users" do
+    @valid_attrs %{
+      full_name: "Jhon doe",
+      email: "jhon.doe@example.com",
+      password_hash: "pass123",
+      role: "student"
+    }
+    @invalid_attrs %{}
+
+    test "create/1 with valid data creates a user" do
+      assert {:ok, %User{} = user} = User.create(@valid_attrs)
+      assert user.full_name == "Jhon doe"
+      assert user.email == "jhon.doe@example.com"
+    end
+
+    test "create_user/1 with invalid data returns error changeset" do
+      assert {:error, %Ecto.Changeset{}} = User.create(@invalid_attrs)
+    end
+
+    test "email must be valid" do
+      attrs = %{@valid_attrs | email: "example"}
+      changeset = User.changeset(%User{}, attrs)
+      refute changeset.valid?
+    end
+  end
+end
diff --git a/apps/core/test/core_test.exs b/apps/core/test/core_test.exs
index 661aff1..3132152 100644
--- a/apps/core/test/core_test.exs
+++ b/apps/core/test/core_test.exs
@@ -1,8 +1,4 @@
 defmodule CoreTest do
   use ExUnit.Case
   doctest Core
-
-  test "greets the world" do
-    assert Core.hello() == :world
-  end
 end
diff --git a/apps/core/test/support/data_case.ex b/apps/core/test/support/data_case.ex
deleted file mode 100644
index bd281e7..0000000
--- a/apps/core/test/support/data_case.ex
+++ /dev/null
@@ -1,46 +0,0 @@
-defmodule Core.DataCase do
-  @moduledoc """
-  This module defines the setup for tests requiring
-  access to the application's data layer.
-
-  You may define functions here to be used as helpers in
-  your tests.
-
-  Finally, if the test case interacts with the database,
-  we enable the SQL sandbox, so changes done to the database
-  are reverted at the end of every test. If you are using
-  PostgreSQL, you can even run database tests asynchronously
-  by setting `use SupervisorService.DataCase, async: true`, although
-  this option is not recommended for other databases.
-  """
-
-  use ExUnit.CaseTemplate
-
-  alias Ecto.Adapters.SQL.Sandbox
-
-  using do
-    quote do
-      import Ecto
-      import Ecto.Changeset
-      import Ecto.Query
-      import Core.DataCase
-    end
-  end
-
-  @app Mix.Project.config()[:app]
-
-  setup tags do
-    for repo <- Application.get_env(@app, :ecto_repos) do
-      :ok = Ecto.Adapters.SQL.Sandbox.checkout(repo)
-    end
-
-    unless tags[:async] do
-      for repo <- Application.get_env(@app, :ecto_repos) do
-        # :ok = Ecto.Adapters.SQL.Sandbox.checkout(repo)
-        Sandbox.mode(repo, {:shared, self()})
-      end
-    end
-
-    :ok
-  end
-end