retention gains do not always equal out by 4th grade. different studies show different results, statistics can be manipulated to support both sides of the issue. as a teacher, if you really think your child might need to be retained at any time, 1st to 2nd is the best time. by the end of second the friendships are deeper and it will be harder for your child to adjust socially. also, children are more aware of who is "smart" and who is "dumb" by second (low child's words, not mine.) retention can be the best gift you could give your child or it could be harmful. it is all in the way it is approached and done. what you should look at is how successful it is in your specific school. how different will the curriculum be for your child? why are they saying he needs retention? is it developmental or is he just not getting it? unless it is developmental, a change in how it is taught would be needed to make a difference. just doing the same thing over will not make a difference unless your child was just not ready to read at a developmental level. i would make an appointment with the principal, 1st grade teacher (if possible), resource teacher, and 2nd grade teacher if possible) to discuss why specifically he is being retained and what they plan on doing to get him at grade level by the end of his second year of first grade. if the plan does not sound like something that will work for him, suggest one that will (extra support, testing, etc.) at our school we have had parents regret the decision to not retain when their child reaches 4th/5th grade because the work load is too much and the child's self esteem is suffering, and we have had children blossom in 3rd and do just fine. you never know. in my own experience the students who were retained in my 2nd grade, they had made huge growth during that extra year, and were proud of themselves. but, we have a special program for those kids who are retained, it is not just the same 1st grade again. there are special pull-outs for them.