What should we do

My fiance has a 9 year old son from a previous relationship from years old. Long story short around april we had him for 2 months due to his mother not having a car. Well from us taking him to school everyday on time the principal pulls us aside one afternoon and informs us that my step son misses school all the time and he recently was gone for a month from school with no explanation. The teachers were worried about him. They show us his attendance records and when he does go to school he isn't in dress code and he comes at 12pm-1pm and school ends at 3pm. Also he is in the 2nd grade for the second time because he wasnt present at school enough. As for the 2017-2018 year (second year of 2nd grade) he comes home with a letter saying that he will be placed in the 3rd grade because they cannot hold hime back again he was literally counted for 50 days out of 177. Can someone give me some advice on what to do. We live in texas and she blocked us from everything. We havent seen or heard from my step son since the beginning of july. We cant afford a lawyer. Any advice? Please