Great comments but I disagree somewhat in that actual "home owners" in Texas pay the vast majority of school (property) taxes - so to the extent that "legal" aliens choose to own homes your statement is true.
School property taxes are based on property value, thus apartment buildings that house a great number of school age children pay the same amount as a private home that may house only one to two children.
One simple fix would be to start taxing property based on the number of bedrooms - in that way families that rent apartments would have to start paying their fair share (legal and/or illegal) towards education
You are correct-only property owners directly pay property taxes based on property value. I think your idea is a good one-either that, or have renters pay a flat rate school tax each year as part of their lease-even those who live in the "projects".
Many people turn a blind eye to the illegal situation, because many people benefit from it. I've known many illegals, and they work like dogs, particularly in construction trades. The employer, even if he pays them the same rate as a legal worker (which he usually doesn't), gets to dodge social security taxes, unemployment taxes, workers comp taxes, health insurance and liability for IOJs. The illegal alien benefits because he gets benefits through welfare and by using the hospital ER as health insurance. You end up with cheaper construction costs, but the savings are offset by higher costs from other industries, most notably, the health care system.