Can't bind to 'ngModel' since it isn't a known property of 'mat-slide-toggle'

ngModel lives in FormsModule of @angular/forms, so import that to your AppModule (or whichever module you are trying to use it in).

Also see this question: Angular 2 two way binding using ngModel is not working

Please try to include FormsModule in your corresponding Module like below

@NgModule({
imports: [ BrowserModule, FormsModule ],
declarations: [ AppComponent ],
bootstrap: [ AppComponent ]
})