Yes. There are a number of online programs, classes, etc. for neurotypical and gifted. Some are free; some are not. E-Learning for kids (http://www.e-learningforkids.org/) is free and has elementary material for English, math, social studies, etc. You might see how that goes. You could also pick up a printed general curriculum guide for less than $10 too and see how that goes and how quickly he accelerates.

My 2e/pg ds8 was similar to your son at that age. He was in a private, gifted school at 5. He quickly accelerated through the pre-k (MA redshirts kids and, for my son, this was the second yr of pre-K due to moving), kindy, 1st grade curriculum. He started to have behavioral problems, fidget, psychosomatic symptoms etc. School wondered if he had ADHD too - which he doesn't. My son was just bored and the school was a mismatch for him.

The long story is that we're un/homeschooling him now.