A reader has noticed that the Wi-Fi at her local library has slowed considerably in recent months, and she's wondering what's causing it: "Is it our computers, bogged down with too much junk, or is it something to do with the library's system?"
Given that you cite multiple computers as exhibiting the same slow connectivity, chances are good it has something to do with the Wi-Fi.
For example, perhaps the router got moved to a location that's blocking some of the signal. (I've been in houses where something in the walls prevented signals from reaching outside a single room.)
It could also be that the router is failing, or that more library patrons are sharing a fixed amount of bandwidth (like more cars on a highway leading to slow-moving traffic). Without having more information, it can be tricky to troubleshoot a problem like this.
However, there's one step worth trying for anyone vexed by sluggish Wi-Fi: try a direct connection to the router. (Actually, that should be your second step; the first is to reset both the modem and router.)
In other words, disable your PC's Wi-Fi, then connect it directly to the router using an Ethernet cable. Windows should automatically detect the new connection and get you online accordingly, though you may have to reboot.
Problem solved? If so, you know there's some kind of Wi-Fi issue to blame. If not, the culprit is probably a bad router, bad router settings, or the Internet connection itself (check with your service provider). Space doesn't permit me to address all these possibilities here, but at least you'll have narrowed down the problem.