I went to high school in Las Vegas and now my kids are in Elementary. I went to a magnet school and loved it. My mom used to teach at an elementary school about seven years ago when it was pretty good. But now I am not that impressed the the district a a whole. My preschooler is in an awsome program through the school district, but I am very disappointed with how my 6 year old schooling is going- 1st grade. I think the problem is the school district is just too big and the schools don't have enough resources. Also, Clark County was one of the highest paying for teachers and now one of the lowest, while the cost of living has increased, so a lot of good teachers left town. There are neighborhoods that are nicer than others that have nicer schools, but I think that it all depends on the teacher, there are great teachers and there are bad teachers.
But on a positive note: they have schools here called magnet schools. Not sure if they have them in TX, but they are public, private schools. Students have to apply to get in, but they are free. They usually specialize in a subject. For example, I went to Advanced Technologies Academy, which is a high school the had 7 programs from law to graphic design. I loved it and learned so much. These schools have smaller classes. There's a few magnet elementary schools, I know one specializes in the arts, there's a technology one where the kids learn how to build robots.
Overall, there are good schools here and great teachers, you just have to find them. My favorite areas of town are in the North West and South west.
You can go to www.ccsd.net then go to magnet schools. Gilbert is the one that specializes in the arts and is located in the NW. Both my friends boys went there and love it. I am currently looking into my options.
Good luck!