Is there a way to change iPhone’s User Agent Info?
You need to use a different web browser.  The paid web browser iCab lets you change the user agent string.  

Whether or not your access to the website is blocked because of the namespace issue mentioned by poster grg is beyond the scope of my answer.

It is not uncommon for education sites to have Windows dependencies built in the site.  You may try some of these browsers to get around Windows dependencies.

Puffin

"Puffin Web Browser is a wicked fast Mobile Flash Browser. Once users experience the thrilling speed of Puffin, regular mobile Internet feels like torture. Puffin Free is the free version of the Puffin family and supports Adobe Flash over cloud during "off-peak hours" from 8AM to 4PM (subject to change without prior notice)"
Free:
https://itunes.apple.com/us/app/puffin-web-browser-free/id472937654?mt=8
Paid:
https://itunes.apple.com/us/app/puffin-web-browser/id406239138?mt=8

VirtualBrowser for Firefox with Flash-browser, Java Player and Add-ons - iPhone Edition
https://itunes.apple.com/us/app/virtualbrowser-for-firefox/id609289360?mt=8

Photon Flash Player for iPad - Flash Video &amp; Games plus Private Web Browser
https://itunes.apple.com/us/app/photon-flash-player-for-ipad/id430200224?mt=8

"java for iPad is now a reality!
If you were ever wondering how to use java for iPad, now you can! With the Virtual-Browser for Firefox App, java for iPad is possible with one simple app download! Virtual-Browser for Firefox App opens up a wide variety of apps and games – like java for iPad – that you can use from your iPad"
http://www.virtualfirefox.com/java-for-ipad

By Splashtop Inc.
Flash Video Web Browser – Full Chrome, IE, Firefox, Safari Compatible
https://itunes.apple.com/us/app/flash-video-web-browser-full/id431331485?mt=8

iPad web browsers set to IE:
http://www.macsinlaw.com/make-your-iphone-ipad-surf-like-internet-explorer-or-fi refox/