Urgent visa question

[Jlee9028]

Hi -- this is my first post so please let me know if I need to provide any other information. I have a few very specific visa questions and I am trying to go through the appropriate embassies and consulates to get them answered, but any insight from other travelers would be very helpful!

I'm an American student at a university in Boston, MA and I am attending a study abroad program in London this fall. I will not have an internship, so will be there merely on a student visitor visa. I am hoping to also study abroad the following semester in Madrid, Dublin or London again but working at an internship. I also hope to stay abroad in between. So my questions:

1) Although I am not a UK citizen, will it be possible for me to obtain a Spanish study/work visa while in London? The consulate website is confusing on this point and I have no way of coming back to the US to apply for the visa before the program starts.

2) If I can obtain the Spanish visa, will it be possible for me to travel to Schengen countries before the start date? My family is hoping to come over for the Christmas holiday, so I know I have to leave the UK for 24 hours before reentering as a tourist. The plan was to go to Switzerland/France and then back to the UK for about 6 days. Then I would probably go to Slovenia, then Turkey before the start of my program. So if I have the visa, can I enter Schengen areas as a tourist if I have a transport ticket to leave before the start of my visa?

3) If I can't obtain the Spanish visa in the UK, would it be possible for me to apply for the Tier 4 student visa while in London? Because the next semester I will have an internship. If so, same question as above basically, could I enter as a tourist for 6 days between the programs as long as I left again and didn't reenter until the start of my visa?

4) If none of the above are possible, what about an Irish visa? Could I apply for one while in the UK? Would there be any restrictions regarding traveling in the UK as a tourist before the start of my Irish visa?
Any help at all would be much appreciated! Sorry if some of this has been answered elsewhere, but I'm trying to cover my bases.

Thank you.