If some of the web-parts are not working for a user whether parent or teacher the most likely cause is due to them having upgraded to Internet Explorer 10 or 11 (IE10, IE11).
Some of the SLG Sharepoint web parts do not work with these browsers
On the page which is not working, press the Alt key which brings up a set of menus across the top of the page.
Go to the Tools menu and choose Compatibility View Settings.
This will show scomis.org as the site.
Click the Add button to add this site.
Close Internet Explorer. Open again and the page should now work.