Early studies indicate that the specific carbohydrate diet (SCD) may improve clinical symptoms and inflammatory biomarkers, but there is not enough high-quality evidence to be sure. N-of-1 (or single-subject repeated cross-over) trials are an ideal method for addressing this important research question. By focusing on the effect of diet for a single individual, N-of-1 studies can successfully identify the impact of each diet on each patient. In this study we will use a series of N-of-1 trials to determine the effectiveness of the SCD in reducing symptoms and inflammation in patients with IBD as compared to a modified SCD and an unrestricted diet at both the individual and population level. We will use a series of N-of-1 trials to determine the effectiveness of the SCD as compared to a modified version of the SCD in reducing symptoms and inflammation in pediatric patients with IBD over a 34-week period. We will recruit 50 patients from 20 ImproveCareNow (ICN) network sites. Participants will use a mobile app to direct their study involvement including collecting outcome data, transitioning between study diets, viewing data and reviewing personal study results. Primary outcomes include patient reported outcomes (PROs) of stool frequency, stool consistency, pain interference and GI symptom severity. We will also examine changes in inflammation via fecal calprotectin and bank stool for future microbiome studies. The N-of-1 design enables us to provide each patient with personalized results on diet impact and also to statistically combine the results to examine effectiveness of the diets at the population level.