If you have hosted B.I.A. SchoolSys on your local server and want to use in local LAN (Local Area Network) network then your B.I.A. SchoolSys hosting machine should have static ip address (not be dynamic assigned by your modem DHCP). Here suppose your server hosting machine have ip address 192.168.1.2 then when you are installing B.I.A. SchoolSys you should type 192.168.1.2/myschool/ not localhost/myschool/ in browser address bar otherwise you cannot access B.I.A. SchoolSys from other computers in your LAN and will redirect to localhost/myschool/ url.
If you have already installed B.I.A. SchoolSys using localhost/myschool/ then you can correct this by editing base_url value in file /application/config/config.php . In this file change localhost to your hosting server static ip address like 192.168.1.2 .