I generally hate disagreeing Hapus, but in this case I'm going to have to :)
The enemy in both Enders Game and Starship Troopers were bugs, and the human protagonists in both were young, but thats pretty much all the similarity I can recall.
In Enders Game, Ender and the others were all children, whereas in Starship Troopers they were young adults/adult.
In Enders Game, there was no face to face combat between Humans and the *******, as the aliens were affectionately known.. it was all ship based, and the human ships were unmanned but remote controlled by the kids via the ansible.
Starship Troopers was actually based upon the novel of the same name by Robert Heinlein, and although I have seen it a couple of times now, I still cant work out whether it was taking itself seriously, or whether it was in essence a sendup! Sooo much GungHo-ness!