Battle for Earth: An Action-Packed Sci-Fi Adventure with Elements of Fantasy (Shockwave Book 1) by Hammer Trollkin

Starship Troopers grit meets X-Men evolution.
When an alien strike on a secret DARPA lab creates Earth’s first superpowered teenagers, a retired Army colonel must lead his own grandkids into a war humanity is losing. Team Shockwave is the only thing standing between Earth and extinction – or something worse.