diff --git a/modules/entity/spec/utils.spec.ts b/modules/entity/spec/utils.spec.ts
index ccbeb7de77..efa0fdeaf2 100644
--- a/modules/entity/spec/utils.spec.ts
+++ b/modules/entity/spec/utils.spec.ts
@@ -32,17 +32,19 @@ describe('Entity utils', () => {
       expect(spy).toHaveBeenCalled();
     });
 
-    xit('should not warn when key does not exist in prod mode', () => {
-      spyOn(ngCore, 'isDevMode').and.returnValue(false);
+    it('should not warn when key does not exist in prod mode', () => {
+      const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(false);
       const spy = spyOn(console, 'warn');
 
       const key = selectIdValue(AClockworkOrange, (book: any) => book.foo);
 
       expect(spy).not.toHaveBeenCalled();
+
+      ngSpy.mockReset();
     });
 
-    xit('should not warn when key is undefined in prod mode', () => {
-      spyOn(ngCore, 'isDevMode').and.returnValue(false);
+    it('should not warn when key is undefined in prod mode', () => {
+      const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(false);
       const spy = spyOn(console, 'warn');
 
       const undefinedAClockworkOrange = { ...AClockworkOrange, id: undefined };
@@ -52,6 +54,8 @@ describe('Entity utils', () => {
       );
 
       expect(spy).not.toHaveBeenCalled();
+
+      ngSpy.mockReset();
     });
   });
 });
diff --git a/modules/store/spec/runtime_checks.spec.ts b/modules/store/spec/runtime_checks.spec.ts
index 55b6923a53..6fc0b0ec1f 100644
--- a/modules/store/spec/runtime_checks.spec.ts
+++ b/modules/store/spec/runtime_checks.spec.ts
@@ -38,8 +38,8 @@ describe('Runtime checks:', () => {
       });
     });
 
-    xit('should disable runtime checks in production by default', () => {
-      spyOn(ngCore, 'isDevMode').and.returnValue(false);
+    it('should disable runtime checks in production by default', () => {
+      const spy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(false);
 
       expect(createActiveRuntimeChecks()).toEqual({
         strictStateSerializability: false,
@@ -49,10 +49,13 @@ describe('Runtime checks:', () => {
         strictActionWithinNgZone: false,
         strictActionTypeUniqueness: false,
       });
+
+      spy.mockReset();
+      spy.mockReturnValue(true);
     });
 
-    xit('should disable runtime checks in production even if opted in to enable', () => {
-      spyOn(ngCore, 'isDevMode').and.returnValue(false);
+    it('should disable runtime checks in production even if opted in to enable', () => {
+      const spy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(false);
 
       expect(
         createActiveRuntimeChecks({
@@ -69,6 +72,9 @@ describe('Runtime checks:', () => {
         strictActionWithinNgZone: false,
         strictActionTypeUniqueness: false,
       });
+
+      spy.mockReset();
+      spy.mockReturnValue(true);
     });
   });
 
diff --git a/modules/store/spec/selector.spec.ts b/modules/store/spec/selector.spec.ts
index a019cc9ef0..ec4c3f4171 100644
--- a/modules/store/spec/selector.spec.ts
+++ b/modules/store/spec/selector.spec.ts
@@ -491,38 +491,44 @@ describe('Selectors', () => {
     });
 
     describe('Warning', () => {
-      xdescribe('should not log when: ', () => {
+      describe('should not log when: ', () => {
         it('the feature does exist', () => {
-          spyOn(ngCore, 'isDevMode').and.returnValue(true);
+          const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(true);
           const selector = createFeatureSelector('featureA');
 
           selector({ featureA: {} });
 
           expect(warnSpy).not.toHaveBeenCalled();
+
+          ngSpy.mockReset();
         });
 
         it('the feature key exist but is falsy', () => {
-          spyOn(ngCore, 'isDevMode').and.returnValue(true);
+          const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(true);
           const selector = createFeatureSelector('featureB');
 
           selector({ featureA: {}, featureB: undefined });
 
           expect(warnSpy).not.toHaveBeenCalled();
+
+          ngSpy.mockReset();
         });
 
         it('not in development mode', () => {
-          spyOn(ngCore, 'isDevMode').and.returnValue(false);
+          const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(false);
           const selector = createFeatureSelector('featureB');
 
           selector({ featureA: {} });
 
           expect(warnSpy).not.toHaveBeenCalled();
+
+          ngSpy.mockReset();
         });
       });
 
-      xdescribe('warning will ', () => {
+      describe('warning will ', () => {
         it('be logged when not in mock environment', () => {
-          spyOn(ngCore, 'isDevMode').and.returnValue(true);
+          const ngSpy = jest.spyOn(ngCore, 'isDevMode').mockReturnValue(true);
           const selector = createFeatureSelector('featureB');
 
           selector({ featureA: {} });
@@ -531,6 +537,8 @@ describe('Selectors', () => {
           expect(warnSpy.calls.mostRecent().args[0]).toMatch(
             /The feature name "featureB" does not exist/
           );
+
+          ngSpy.mockReset();
         });
 
         it('not be logged when in mock environment', () => {