I have 4 monitors in my home and all of them support VGA/DVI, and out of 5 TV's in the house 3 support VGA and HDMI, all of the TV's have composite and all but 1 has component available
The big problem is that to add VGA to the Raspi would likely cost most of what it would cost to buy a digital to analog converter to convert a monitor that only has VGA.
Understandingly I know that there are many VGA only monitors still out there, I have VGA/DVI monitors as I update my equipment as needed and these newer monitors cost less to operate, (power bill say's this is true.)
I have not looked at school equipment in a long time but I believe this may be the case with them as well in that some schools have updated and have monitors that will use at least DVI and some schools will still have VGA only equipment.
Either way though you will pay a cost to upgrade your monitor or buy an adapter to provide the VGA and of course it is up to you which is more cost effective.
Personally if I did not have any thing but VGA equipment I would choose a new monitor (all of my monitors allow you to choose an input or auto select and this increases flexibility as you can have one system using the VGA and one system using the DVI and switch between them) as adapters are useful item but are also only a fix for a bigger problem in the end.(and most of the adapters almost cost what a monitor does anyway)IMHO
I have a 19" TV that is being multitasked as it is attached to a 8 port KVM for the VGA input and that serves 3 computers and a 4th computer is attached to the HDMI port via a HDMI to DVI converter cable(video card does not support VGA only Dual DVI) and it has a Roku attached to the component port and speakers and then is hooked to the cable for regular TV via a regular cable connector and that still leaves a composite port and a S-video port open.
If you are more worried about ,spelling, punctuation or grammar you have probably already missed the point so please just move on.