diff --git a/crates/web-sys/README.md b/crates/web-sys/README.md
index cb69fa2e..9241f682 100644
--- a/crates/web-sys/README.md
+++ b/crates/web-sys/README.md
@@ -221,11 +221,11 @@ bindings are fully working and have full test coverage.
  - [ ] HTMLMenuItemElement.webidl
  - [ ] HTMLMetaElement.webidl
  - [ ] HTMLMeterElement.webidl
- - [ ] HTMLModElement.webidl
+ - [x] HTMLModElement.webidl
  - [ ] HTMLObjectElement.webidl
- - [ ] HTMLOListElement.webidl
- - [ ] HTMLOptGroupElement.webidl
- - [ ] HTMLOptionElement.webidl
+ - [x] HTMLOListElement.webidl
+ - [x] HTMLOptGroupElement.webidl
+ - [x] HTMLOptionElement.webidl
  - [x] HTMLOptionsCollection.webidl
  - [x] HTMLOutputElement.webidl
  - [x] HTMLParagraphElement.webidl
diff --git a/crates/web-sys/tests/wasm/element.js b/crates/web-sys/tests/wasm/element.js
index 6e0d5ccb..583fca65 100644
--- a/crates/web-sys/tests/wasm/element.js
+++ b/crates/web-sys/tests/wasm/element.js
@@ -14,6 +14,10 @@ export function new_button() {
   return document.createElement("button");
 }
 
+export function new_del() {
+    return document.createElement("del");
+}
+
 export function new_div() {
     return document.createElement("div");
 }
@@ -22,6 +26,10 @@ export function new_form() {
   return document.createElement("form");
 }
 
+export function new_food_options_collection() {
+    return new_select_with_food_opts().options;
+}
+
 export function new_head() {
   return document.createElement("head");
 }
@@ -42,8 +50,16 @@ export function new_input() {
     return document.createElement("input");
 }
 
-export function new_food_options_collection() {
-    return new_select_with_food_opts().options;
+export function new_ins() {
+    return document.createElement("ins");
+}
+
+export function new_olist() {
+    return document.createElement("ol");
+}
+
+export function new_optgroup() {
+    return document.createElement("optgroup");
 }
 
 export function new_output() {
diff --git a/crates/web-sys/tests/wasm/main.rs b/crates/web-sys/tests/wasm/main.rs
index 59efa62a..4d386493 100644
--- a/crates/web-sys/tests/wasm/main.rs
+++ b/crates/web-sys/tests/wasm/main.rs
@@ -25,6 +25,10 @@ pub mod hr_element;
 pub mod html_element;
 pub mod html_html_element;
 pub mod input_element;
+pub mod mod_elements;
+pub mod olist_element;
+pub mod optgroup_element;
+pub mod option_element;
 pub mod options_collection;
 pub mod output_element;
 pub mod paragraph_element;
diff --git a/crates/web-sys/tests/wasm/mod_elements.rs b/crates/web-sys/tests/wasm/mod_elements.rs
new file mode 100644
index 00000000..f7dacdff
--- /dev/null
+++ b/crates/web-sys/tests/wasm/mod_elements.rs
@@ -0,0 +1,28 @@
+use wasm_bindgen_test::*;
+use wasm_bindgen::prelude::*;
+use web_sys::HtmlModElement;
+
+#[wasm_bindgen(module = "./tests/wasm/element.js")]
+extern {
+    fn new_del() -> HtmlModElement;
+    fn new_ins() -> HtmlModElement;
+}
+
+#[wasm_bindgen_test]
+fn test_mod_elements() {
+    let del = new_del();
+
+    del.set_cite("https://www.rust-lang.org/en-US/");
+    assert_eq!(del.cite(), "https://www.rust-lang.org/en-US/", "Option should have the cite URI we gave it.");
+
+    del.set_date_time("Thu Aug 02 2018 18:02:56 GMT-0500 (Central Daylight Time)");
+    assert_eq!(del.date_time(), "Thu Aug 02 2018 18:02:56 GMT-0500 (Central Daylight Time)", "Option should have the date_time we gave it.");
+
+    let ins = new_ins();
+
+    ins.set_cite("https://www.rust-lang.org/en-US/");
+    assert_eq!(ins.cite(), "https://www.rust-lang.org/en-US/", "Option should have the cite URI we gave it.");
+
+    ins.set_date_time("Thu Aug 02 2018 18:02:56 GMT-0500 (Central Daylight Time)");
+    assert_eq!(ins.date_time(), "Thu Aug 02 2018 18:02:56 GMT-0500 (Central Daylight Time)", "Option should have the date_time we gave it.");
+}
\ No newline at end of file
diff --git a/crates/web-sys/tests/wasm/olist_element.rs b/crates/web-sys/tests/wasm/olist_element.rs
new file mode 100644
index 00000000..411b73cf
--- /dev/null
+++ b/crates/web-sys/tests/wasm/olist_element.rs
@@ -0,0 +1,34 @@
+use wasm_bindgen_test::*;
+use wasm_bindgen::prelude::*;
+use web_sys::HtmlOListElement;
+
+#[wasm_bindgen(module = "./tests/wasm/element.js")]
+extern {
+    fn new_olist() -> HtmlOListElement;
+}
+
+#[wasm_bindgen_test]
+fn test_olist_element() {
+    let olist = new_olist();
+
+    olist.set_reversed(true);
+    assert_eq!(olist.reversed(), true, "Olist should be reversed after we set it to be reversed.");
+
+    olist.set_reversed(false);
+    assert_eq!(olist.reversed(), false, "Olist should not be reversed after we set it to be not reversed.");
+
+    olist.set_start(23);
+    assert_eq!(olist.start(), 23, "Olist should have the start value we gave it.");
+
+    olist.set_type("A");
+    assert_eq!(olist.type_(), "A", "Olist should be type 'A' after we set it to be type 'A'.");
+
+    olist.set_type("I");
+    assert_eq!(olist.type_(), "I", "Olist should be type 'I' after we set it to be type 'I'.");
+
+    olist.set_compact(true);
+    assert_eq!(olist.compact(), true, "Olist should be compact after we set it to be compact.");
+
+    olist.set_compact(false);
+    assert_eq!(olist.compact(), false, "Olist should not be compact after we set it to be not compact.");
+}
\ No newline at end of file
diff --git a/crates/web-sys/tests/wasm/optgroup_element.rs b/crates/web-sys/tests/wasm/optgroup_element.rs
new file mode 100644
index 00000000..1a7dccfc
--- /dev/null
+++ b/crates/web-sys/tests/wasm/optgroup_element.rs
@@ -0,0 +1,22 @@
+use wasm_bindgen_test::*;
+use wasm_bindgen::prelude::*;
+use web_sys::HtmlOptGroupElement;
+
+#[wasm_bindgen(module = "./tests/wasm/element.js")]
+extern {
+    fn new_optgroup() -> HtmlOptGroupElement;
+}
+
+#[wasm_bindgen_test]
+fn test_optgroup_element() {
+    let optgroup = new_optgroup();
+
+    optgroup.set_disabled(true);
+    assert_eq!(optgroup.disabled(), true, "Optgroup should be disabled after we set it to be disabled.");
+
+    optgroup.set_disabled(false);
+    assert_eq!(optgroup.disabled(), false, "Optgroup should not be disabled after we set it to be not-disabled.");
+
+    optgroup.set_label("Group of options below");
+    assert_eq!(optgroup.label(), "Group of options below", "Optgroup should have the label we gave it.");
+}
\ No newline at end of file
diff --git a/crates/web-sys/tests/wasm/option_element.rs b/crates/web-sys/tests/wasm/option_element.rs
new file mode 100644
index 00000000..6dddb0f9
--- /dev/null
+++ b/crates/web-sys/tests/wasm/option_element.rs
@@ -0,0 +1,44 @@
+use wasm_bindgen_test::*;
+use wasm_bindgen::prelude::*;
+use web_sys::HtmlOptionElement;
+
+#[wasm_bindgen_test]
+fn test_option_element() {
+    let option = HtmlOptionElement::new(
+      "option_text",
+      "option_value",
+      false,
+      true
+    ).unwrap();
+
+    option.set_disabled(true);
+    assert_eq!(option.disabled(), true, "Option should be disabled after we set it to be disabled.");
+
+    option.set_disabled(false);
+    assert_eq!(option.disabled(), false, "Option should not be disabled after we set it to be not-disabled.");
+
+    assert!(option.form().is_none(), "Our option should not be associated with a form.");
+
+    option.set_label("Well this truly is a neat option");
+    assert_eq!(option.label(), "Well this truly is a neat option", "Option should have the label we gave it.");
+
+    option.set_default_selected(true);
+    assert_eq!(option.default_selected(), true, "Option should be default_selected after we set it to be default_selected.");
+
+    option.set_default_selected(false);
+    assert_eq!(option.default_selected(), false, "Option should not be default_selected after we set it to be not default_selected.");
+
+    option.set_selected(true);
+    assert_eq!(option.selected(), true, "Option should be selected after we set it to be selected.");
+
+    option.set_selected(false);
+    assert_eq!(option.selected(), false, "Option should not be selected after we set it to be not selected.");
+
+    option.set_value("tomato");
+    assert_eq!(option.value(), "tomato", "Option should have the value we gave it.");
+
+    option.set_text("potato");
+    assert_eq!(option.text(), "potato", "Option should have the text we gave it.");
+
+    assert_eq!(option.index(), 0, "This should be the first option, since there are no other known options.");
+}
\ No newline at end of file