We went about 5 years ago, staying on the Canadian side at the KOA on Lundy's Lane. There was a city bus that stopped at the campground entrance multiple times an hour, making going to the falls very easy.
I am assuming they still have Maid of the Mist boats? We thought it was fun to do. You get complimentary rain ponchos and the boats go right into the mist from the falls.
We had dinner at the Skylon Tower - I highly recommend it! Very cool, very good food. Spectacular view overlooking the falls.
I have no idea if you'd be interested, but I took my son and his friend to the Canadian hydro power station a couple miles down the river. You take an elevator and go something like 27 stories down to a viewing area / museum to check out the hydro generators. I enjoyed it!
There is actually a ton of stuff to do and see in the Niagara area. It is a VERY built up tourist area - not at all woodsy like the pictures show. The Canadian side seems to have more touristy things to do.
Have fun!