We are looking for accomodation in July, in London and are traveling with teenagers. Any ideas?
Depending on how long you're staying you might consider an apartment rental. That way you get a little extra space, your own kitchen (which can save A LOT on food since London is quite expensive) and some other benefits. My parents did that with+- us when I went there at age 15 and it worked quite well.
Irene, If you're looking for budget, I used hotwire.com. (Knock on wood) I've been really lucky getting hotels like Hilton, Sheraton, and Crowne Plaza for $126 per night or lower. This June I need just a 1 night stay near Heathrow and got the Sheraton for $89.
The unfortunate part of hotwire is you don't know the name until you pay. The good part is you pay in advance so its one less thing to worry about.