Full Metal Panic! The Second Raid, Code Geass: Hangyaku no Lelouch Recommendations
Code Geass and FMP are similar because of the "mecha" theme. Code Geass is actually fighting using those "robots" like the one in FMP. You should give them both a try.
Aside from the giant mechs, the two are fantastic military dramas with a couple love interests for the main character and great bad guys. Also included are main characters in high school.