They Came From Below — Blake Nelson

Seventeen-year-old Emily and her best friend Reese can't wait for summer vacation on Cape Cod. Every year, it's the same thing: high hopes that they may finally hook up with some cool guys...and it never happens. But this year, they're sure it's going to be different. So it's totally amazing when out of nowhere they meet two unbelievably adorable boys who are just too cute to be true! Which, they soon discover, may be the case. A lot of odd things happen when Steve and Dave are around. Reese figures it's because they're not from around here. So where are they from, France? Well, not quite...
Summoned from the depths of the sea by the dire threat of global pollution, friendly aliens "Steve and Dave" have manifested themselves in human form and come ashore in a last desperate effort to save the oceans.