I understand that U-46 does not have a good reputation; I think it has more to do with the community than the schools and curriculum. I work in the district; I have worked in elementary schools in both Streamwood and Elgin, and have been with the district about 7 years. Their curriculum is very good, and I have never seen a district offer more training to their teachers in the latest and most up to date and best practices. To be quite honest, I live in Mt. Prospect, and was very disappointed in the curriculum they have in the early elementary level; they seem to be about 6 years behind u-46, at least in literacy.
On the other hand, I would hesitate to send my kids to my school district when they got older, mostly because there are problems with gangs in the community. However, gangs are a problem that faces almost every community; it's just to what extent. I also taught in a middle school in the district, and was disappointed in their curriculum and emphasis. Keep in mind, too, that u-46 is very large, and no matter the school or the district, a LOT depends on the principal of the school, and your child's particular teacher.
I have worked in a lot of schools here and in other states, and in every school, I would feel comfortable having my child learn at the school in which I taught, if I could hand-pick the teacher at each grade level.
Test scores only tell part of the story; keep in mind that when a school serves a population which includes students living in poverty, learning in a language which is not their first, and sometimes with parents who can't help their children for a myriad of reasons, this is going to make the "test scores" look poor; Test scores do not always reflect the teaching OR the curriculum. If test scores were poor at a high-income school, I'd worry about the school. But u-46 has a huge range of incomes and communities it serves, many low-income.
I guess my advice in the end is to go and visit the elementary school your children will attend, no matter what district. The same goes for middle and high schools, because there can be a huge difference between elementary, middle and high schools in the same district.
Sorry to ramble...