I've just released a set of five lesson plans centered around the present perfect simple. It's quite a difficult tense to teach, but I think these lesson plans work quite well. I've designed them for private tutorial use and they are loaded onto a web platform. If you would like an account to check them out (and hopefully use them in your own lessons) you can get in touch either by sending me a PM or the contact form on our site (http://www.off2class.com). I would love to hear feedback. We wrote a short posting about our approach here (http://www.off2class.com/?p=4074).