I personally think that's great. If you're moving forward and your child is happy and being challenged in some way, then carry on.
We don't do much more than that on average. But my kids take on a lot of their own exploration, learning, and reading. We do a lot of field trips and outings.
My 9 year old 3rd grader spends 2-3 hours typically. My 5 year old is literally maybe 1/2 hour with maybe another 1/2 hour read aloud time. We usually have 1 longer day a week.
I totally agree with Wyldkat. If you start doing the math on social, extra curricular, educational games, free reading, etc. it really adds up. Just because you aren't sitting at a table producing paper work and output doesn't mean a lot of learning isn't just happening on it's own. My kids aren't allowed any recreational TV or computer between get up time and 3 pm. So anything they're doing during those hours tends to be learning based, whether they know it is or not. Yesterday my 5 year old "engineered" a village for her beanie baby cats in out living room out of a pile of boxes. She had me cutting doors and hooking them up. My 9 year old lately has been playing with magic tricks (hey that's research and small motor skills!) and Rube Goldberg machines (physics!).
If you think about how much time the average child in a classroom is actually engaged and learning something new, it really wouldn't be more than that generally.
