Telephone interview here. Homerton College.
First, I was asked general questions like "Why Cambridge?" and "Tell me a little about yourself." The following question, IIRC, was "Describe a sort algorithm to me." That was very easy. Then, I was asked how many comparisons are necessary in a sort algorithm. I didn't know that, but I said that it could be n-1 + n-2 + n-3... so the sum of all consecutive integers until n-1, which has it's own formula which I knew from math class. I was told that was a good estimate, but I have no idea if it really were (can anyone clarify please?). I was explained several aspects of the course, such as the 25% NatSci thing, and I was told I wold take Physics (which is my only NatSci IB subject). I was asked some physics questions, like if I had covered thermodynamics and if I had done any lab work. I answered yes to both of them. So then I was asked to describe the most recent experiment I did. I recalled one experiment in which we investigaded what factors affected the period of a pendulum, and also tried to come up with a mathematical expression for the period. I was then asked if the period depended on the mass. I answered "no, I don't think it does", and then I was asked if I understood why. My mind went blank there, so I answered I didn't really know, and then I was told it was okay and I was explained the answer.
Before the physics question, I was asked what was my favorite subject, and I answered maths. I was told that unfortunately we were not going to be able to make problems over the phone. I was dissapointed because I was pretty confident with math problems. I was then asked if I knew how to do some operations with matrices, which I do know. I was also asked if we had covered any set theory, which I answered no, but now that I think abaout it, I think I should've said that we covered Venn diagrams and basic operations like union, intersection, and complement. I was also asked if I knew how a chip worked. I really didn't, and I made something out which was totally stupid ("it probably has to do with 0's and 1's", I answered). I was asked another question about the Internet, which I couldn't understand completely because my phone started making some strange noise, I asked for repetition, but I still didn't get it, so I answered "like search engines, for example?" and I think that had something to do with the question, so I was then asked if I knew how one works. I answered that HTML code has some tags which contain certain keywords, and that the search engine looks them up. I totally missed the point about "indexing" and links (one site leads to other similar sites), although I could have really answered that if I wasn't under pressure. I was also asked if I knew about how many sites an engine searches, and I answered they were billions (which I remembered seeing at the bottom of Google), which I'm pretty sure was correct. I was also asked a little about my written work, which was my IB Dossier for a program I had written in Pascal for my Computer Science course. I was mainly asked about how I tested it. I was finally asked about what I liked to do outside class.
I really have no idea of how I did. At some points I couldn't understand correctly because of the phone, and so my answers were vague, and that was worsened by the fact that English is not my native language.
BTW, I did not took the TSA (I was never asked anything about it). Do you guys think that is bad? I've started to worry about it... perhaps they did not ask for me to take it because I had no chance of admission.