diff --git a/packages/ember-glimmer/lib/utils/references.js b/packages/ember-glimmer/lib/utils/references.js
index 75ac4b368e0..762b6eddea5 100644
--- a/packages/ember-glimmer/lib/utils/references.js
+++ b/packages/ember-glimmer/lib/utils/references.js
@@ -220,7 +220,7 @@ export class NestedPropertyReference extends PropertyReference {
       return parentValue.length;
     }
 
-    if (typeof parentValue === 'object' && parentValue) {
+    if ((typeof parentValue === 'object' || typeof parentValue === 'function') && parentValue) {
       if (MANDATORY_SETTER) {
         watchKey(parentValue, _propertyKey);
       }
@@ -322,7 +322,7 @@ export class SimpleHelperReference extends CachedReference {
         return NULL_REFERENCE;
       } else if (result === undefined) {
         return UNDEFINED_REFERENCE;
-      } else if (typeof result === 'object') {
+      } else if (typeof result === 'object' || typeof result === 'function') {
         return new RootReference(result);
       } else {
         return PrimitiveReference.create(result);
@@ -407,7 +407,7 @@ export class UnboundReference extends ConstReference {
       return NULL_REFERENCE;
     } else if (value === undefined) {
       return UNDEFINED_REFERENCE;
-    } else if (typeof value === 'object') {
+    } else if (typeof value === 'object' || typeof result === 'function') {
       return new UnboundReference(value);
     } else {
       return PrimitiveReference.create(value);
diff --git a/packages/ember-metal/lib/property_set.js b/packages/ember-metal/lib/property_set.js
index bb316c643b8..47be6434d3a 100644
--- a/packages/ember-metal/lib/property_set.js
+++ b/packages/ember-metal/lib/property_set.js
@@ -68,7 +68,6 @@ export function set(obj, keyName, value, tolerant) {
 
     propertyDidChange(obj, keyName, meta);
   }
-
   return value;
 }
 
diff --git a/packages/ember-metal/lib/tags.js b/packages/ember-metal/lib/tags.js
index b5dbd55c52e..ebd4076e586 100644
--- a/packages/ember-metal/lib/tags.js
+++ b/packages/ember-metal/lib/tags.js
@@ -13,7 +13,7 @@ function makeTag() {
 }
 
 export function tagForProperty(object, propertyKey, _meta) {
-  if (typeof object !== 'object' || object === null) { return CONSTANT_TAG; }
+  if ((typeof object !== 'object' && typeof object !== 'function') || object === null) { return CONSTANT_TAG; }
 
   let meta = _meta || metaFor(object);
   if (meta.isProxy()) {
@@ -28,7 +28,7 @@ export function tagForProperty(object, propertyKey, _meta) {
 }
 
 export function tagFor(object, _meta) {
-  if (typeof object === 'object' && object !== null) {
+  if (typeof object === 'object' && object !== null || typeof object === 'function') {
     let meta = _meta || metaFor(object);
     return meta.writableTag(makeTag);
   } else {
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 36304f07cd8..d0fc69f7692 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -14,7 +14,7 @@ import {
 let handleMandatorySetter;
 
 export function watchKey(obj, keyName, meta) {
-  if (typeof obj !== 'object' || obj === null) { return; }
+  if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) { return; }
 
   let m = meta || metaFor(obj);
   let count = m.peekWatching(keyName) || 0;
@@ -81,9 +81,8 @@ if (MANDATORY_SETTER) {
 }
 
 export function unwatchKey(obj, keyName, _meta) {
-  if (typeof obj !== 'object' || obj === null) {
-    return;
-  }
+  if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) { return; }
+
   let meta = _meta || peekMeta(obj);
 
   // do nothing of this object has already been destroyed
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index fb76aaa84f1..1fbb6cbc1a8 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -16,7 +16,7 @@ export function makeChainNode(obj) {
 }
 
 export function watchPath(obj, keyPath, meta) {
-  if (typeof obj !== 'object' || obj === null) { return; }
+  if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) { return; }
   let m = meta || metaFor(obj);
   let counter = m.peekWatching(keyPath) || 0;
 
@@ -27,7 +27,7 @@ export function watchPath(obj, keyPath, meta) {
 }
 
 export function unwatchPath(obj, keyPath, meta) {
-  if (typeof obj !== 'object' || obj === null) { return; }
+  if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) { return; }
   let m = meta || peekMeta(obj);
   if (m === undefined) { return; }
   let counter = m.peekWatching(keyPath) || 0;
diff --git a/packages/ember-metal/lib/watching.js b/packages/ember-metal/lib/watching.js
index d05bdbb9713..0bf5c5028d0 100644
--- a/packages/ember-metal/lib/watching.js
+++ b/packages/ember-metal/lib/watching.js
@@ -42,7 +42,7 @@ function watch(obj, _keyPath, m) {
 export { watch };
 
 export function isWatching(obj, key) {
-  if (typeof obj !== 'object' || obj === null) {
+  if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) {
     return false;
   }
   let meta = peekMeta(obj);