diff --git a/lib/floki.ex b/lib/floki.ex
index 8353b7c0..de1af63c 100644
--- a/lib/floki.ex
+++ b/lib/floki.ex
@@ -570,8 +570,7 @@ defmodule Floki do
   def text(html, opts \\ []) do
     defaults = [deep: true, js: false, style: true, sep: "", include_inputs: false]
 
-    # We can use `Keyword.validate!` when require Elixir 1.13
-    opts = Keyword.merge(defaults, opts)
+    opts = Keyword.validate!(opts, defaults)
 
     cleaned_html_tree =
       html
@@ -617,6 +616,8 @@ defmodule Floki do
   end
 
   def children({_, _, _} = html_node, opts) do
+    opts = Keyword.validate!(opts, include_text: true)
+
     children(html_node, include_text: opts[:include_text])
   end
 
diff --git a/lib/floki/raw_html.ex b/lib/floki/raw_html.ex
index 42c4fe84..41e72b9c 100644
--- a/lib/floki/raw_html.ex
+++ b/lib/floki/raw_html.ex
@@ -34,17 +34,19 @@ defmodule Floki.RawHTML do
   @encoder &Floki.Entities.encode/1
   @no_encoder &Function.identity/1
 
-  def raw_html(html_tree, options) do
+  def raw_html(html_tree, opts) do
+    opts = Keyword.validate!(opts, encode: true, pretty: false)
+
     encoder =
-      case Keyword.fetch(options, :encode) do
-        {:ok, true} -> @encoder
-        {:ok, false} -> @no_encoder
+      case opts[:encode] do
+        true -> @encoder
+        false -> @no_encoder
         :error -> default_encoder()
       end
 
     padding =
-      case Keyword.fetch(options, :pretty) do
-        {:ok, true} -> %{pad: "", pad_increase: "  ", line_ending: "\n", depth: 0}
+      case opts[:pretty] do
+        true -> %{pad: "", pad_increase: "  ", line_ending: "\n", depth: 0}
         _ -> :noop
       end
 
diff --git a/test/floki_test.exs b/test/floki_test.exs
index 0bfb66a5..876716c0 100644
--- a/test/floki_test.exs
+++ b/test/floki_test.exs
@@ -1606,8 +1606,14 @@ defmodule FlokiTest do
 
     assert Floki.children(html_node) == expected
     assert Floki.children(html_node, include_text: true) == expected
-    assert Floki.children(html_node, include_text: true, unknown_option: true) == expected
-    assert Floki.children(html_node, unknown_option: true) == expected
+
+    assert_raise ArgumentError, fn ->
+      Floki.children(html_node, include_text: true, unknown_option: true)
+    end
+
+    assert_raise ArgumentError, fn ->
+      Floki.children(html_node, unknown_option: true)
+    end
   end
 
   test "returns the children elements of an element without the text" do
@@ -1622,7 +1628,10 @@ defmodule FlokiTest do
     ]
 
     assert Floki.children(elements, include_text: false) == expected
-    assert Floki.children(elements, include_text: false, unknown_option: true) == expected
+
+    assert_raise ArgumentError, fn ->
+      Floki.children(elements, include_text: false, unknown_option: true)
+    end
   end
 
   test "returns nil if the given html is not a valid tuple" do