I never took DS to sleep school but I share your exhaustion pain. DS never slept for more than 3 hours in a row until about 9 months, and didn't sleep thru the night until about 3 years. His bedtimes varied from 8:30 to 11pm, and wake ups from 7 to 8 am. If he had a day sleep he could stay awake until midnight. I went back to work when he was 5 months old. The sleep deprivation was insane. I still don't know how I functioned.