My iPod Touch is having WiFi issues?

When I am at school, I try to connect to the WiFi. Usually it comes up with a “Log In” page saying something with three options. They are “continue, see details, and cancel.” When I hit “continue, and then “connect” on the Linksys page, it then closes and I have WiFi. Now, it just goes straight to the connecting page, and when I click it, it either doesn’t give me WiFi or it says I’m connected but I don’t recieve the WiFi.