Congrats on puppy class. I hope he does really well!

Going down the stairs can be really scary for a little puppy. I wouldn't force him, or he might become traumatized by it. Cocoa, or Shih Tzu mix, fell down the stairs once, and for years after that we'd sometimes hear her crying at the top of the stairs until we encouraged her down gently, or carried her down. Once he's a bigger dog he shouldn't have any trouble, but it can be really scary going headfirst down a flight of stairs when you're little.