Asking for Letters of Recommendation?

<p>So I'm a rising senior, and I guess it's about time that I start asking my teachers for recommendations for college apps. The problem is, I have no idea how to start.</p>

<p>I'm been reading around online, and the general consensus seems to be "in-person > over email", but I'm very shy, especially when it comes to talking to teachers one-on-one, so I was wondering if sending a polite email over the summer asking them if they could write me a strong letter and explaining why I liked their class would be appropriate?</p>

<p>Also, wouldn't asking over the summer give them more than enough time to actually write the letter? I'm worried that asking at the beginning of next year would not only give them the opportunity to forget me, but also be a bit short notice.</p>