nice job. I'm also 14 and into web design too. for the life mac site, the background for the navigation is a bit harsh on the eyes and the blurred edges look a bit dodgy. other than that it's not bad. the more micro site is pretty good, although the glows and shadows are a bit dodgy looking.
I feel sorry for you having to suffer with a 'teacher' referring to front page as a web design app. that's like calling a daewoo a fast car. here's a site i recently designed ( i actually did it over the past day or so). check it out -
http://www.scotmac.com.au