According to angular-2 select, the options take in items array
Also, use ng-2 select instead of angular-2 select
import {SelectModule} from 'ng2-select'
According to its documentation here, official documentation it requires,
items - (Array<any>) - Array of items from which to select. Should be an array of objects with id and text properties. As convenience, you may also pass an array of strings, in which case the same string is used for both the ID and the text.
So, your object shoud be either,
category:any = [{ id: 'school', text:'school'},{id: 'college', text:'college'}];
<ng-select [items]="category" [(ngModel)]="category.id" name="category" class='filterDropDown' placeholder="Category" notFoundMsg="No Category Found">
</ng-select>
or
category:any = ['school', 'college'];
<ng-select [items]="category" [(ngModel)]="category" name="category" class='filterDropDown' placeholder="Category" notFoundMsg="No Category Found">
</ng-select>
PS: You can use angular2-select change the object to,
import {SelectModule} from 'angular2-select'
It uses, value and label and use same [options] in html
category:any = [{ label: 'school', value:'school'},{label: 'college', value:'college'}];
<ng-select [options]="category" [(ngModel)]="category.label" name="category" class='filterDropDown' placeholder="Category" notFoundMsg="No Category Found">
</ng-select>