spaghetti, I think one of the confusions many individuals and districts alike have is that LRE is not synonymous with general ed. LRE is different for each student depending on their needs. LRE for some intellectually impaired students is a sub sep life skills classroom working on functional academics and ADLs, with integration into the general population occurring mainly during travel training on a public transportation system. LRE for some GT students is a sub sep GT classroom with accelerated curriculum. And yes, LRE for some LD students is a general ed classroom with co-taught or push-in special education supports.
aquinas, you make a good point that there are economies of scale involved in congregated classrooms at both ends of the spectrum, such that budgetary investment in inclusion is an ideological value, not necessarily a true cost-savings. This is one of the reasons that services for exceptionalities at both ends are often better in large urban districts than in small, moderately affluent suburban districts. I see the small districts around the mid-size city from which many of my students are drawn spending 10s to 100s of thousands per kid on outplacements for low-incidence disabilities, while the mid-size city can keep those services in-house, because they have enough to make a cohort, and it becomes cost-effective to hire district professionals. I also see those same small districts keeping mildly disabled students (of many different kinds of disabilities, not just intellectual) in fairly restrictive settings, because they don't have the resources to staff that many co-taught classrooms, so instead, they staff a single generic resource room, where all different disabilities are serviced, not necessarily in a targeted way.
Unfortunately, there are more districts than I would like out there selling inclusion as simultaneously a cost-savings and a moral good. It might be a moral good (implemented thoughtfully), but it has the potential for being a cost-saving only when general and special education staff are adequately trained for its use--which, of course, costs money, too.
On a side note, only about 15% (13%, in the 2015-2016 SY) of the school-age population is identified as special education in the US. Once this number starts pushing 20% or more, one ought to ask the question of how adequate core instruction is. (6.7% were ID'd GT in the 2005-2006 SY, which appears to be the most recent year available at NCES.)
