Stair ideas? Could we do the slide for the stair?

For the slide in the house is possible, but make sure the safety is first.
Usually with the new build house or renovation that build the new stairs case, you could ask the designer add the slide part into the stair at the relaxing places of your kids, usually nearby basement.

For the exist stair in the house you could put the plastic one but make sure it can be easy to remove because the slide occupy the room of the stair for inconvenient in go up and down plus make the ugly look for you house.

More ideas for your first stair in the woods, read more this article:

Stair ideas? For the carpet stair to the stair in the woods.