I have gone through Davidson's, Hoagies', and dozens of other archived articles and references and haven't yet found a (preferably peer reviewed) article that touches on recommended learning environments for gifted children who struggle socially.
I find articles and chapters that focus on or touch on the social and emotional struggles of gifted children. And I find information about how not having an IEP or at least an informal IEP in place, will not address academic or social needs of Gifted Children. But I can't seem to find anything that outlines experiments in gifted classroom structures, and the results of these tests.
I am certain that these conversations exits, I just haven't run across them yet. Can anyone here point me in the right direction?
TIA!

It is my understanding that there is nothing about being gifted which means a child will struggle socially.

However some children are twice-exceptional (gifted and also presenting with a learning difference or learning disability such as ADD/ADHD and/or Autism Spectrum Disorder(ASD)) and may need or benefit from direct teaching of social skills as a result of their disability. As these children may present with social difficulty and/or behavior problems, these issues may be addressed with an IEP/504. Depending upon what you are seeking, Wrightslaw may be a source of information.

If you are seeking lists of recommended books and/or courses/lessons which parents have found helpful, there are threads which discuss these resources. These would be based on individual experiences - anecdotal evidence.

If you are seeking to review literature which documents research "experiments" on human subjects (empirical evidence), some may find a controlled study on children's social development a bit unethical when it comes to creating a control group of children selected to NOT benefit.

My two cents: a recommended learning environment for a child with social skills deficits (whether the child is gifted or not) would be an environment in which the teachers have knowledge of disabilities and direct-teaching of social skills, with an approach of affirmation and validation (as opposed to shaming). The website Social Thinking includes a webpage of published peer-reviewed papers.

On the other hand, if a gifted child is a social isolate simply because same-age classmates are comparatively behind in humor development, reading, vocabulary, well-rounded interests, and making connections between various ideas/concepts... then the preferred learning environment for the gifted child's continued social development may be among intellectual and academic peers, such as:
- a multi-age classroom in which pupils are cluster grouped by readiness and ability,
- single subject acceleration (SSA),
- whole-grade acceleration,
- weekend, after-school, or summertime special interest activity groups.
Teachers with an understanding of giftedness, and an approach of affirmation and validation (as opposed to shaming) would be key.

These thoughts about social inclusion mirror the research by Miraca Gross, discussed in this old post.

If you could be more clear about what you are seeking and your purpose, possibly more members could post helpful replies.

Try these. Both of the reviews suggest that the social challenges commonly associated with giftedness have more to do with environment than any characteristics innate to gifted. In other words, gifted kids in the regular classroom experience more social challenges than those who are grouped with like peers (shocking, I know! But it's the exact opposite of what our school system deeply believes).

Coleman, Laurence, J., Micko, Karen, J., Cross, & Tracy, L. (2015). Twenty-Five Years of Research on the Lived Experience of Being Gifted in School. Journal for the Education of the Gifted, 38(4), 358–376. http://doi.org/10.1177/0162353215607322

Coleman, L. J., & Cross, T. L. (2014). Is Being Gifted a Social Handicap? Journal for the Education of the Gifted, 37(1), 5–17. http://doi.org/10.1177/0162353214521486

Neihart, M. (2007). The Socioaffective Impact of Acceleration and Ability Grouping: Recommendations for Best Practice. Gifted Child Quarterly, 51(4), 330–341. http://doi.org/10.1177/0016986207306319