This is the living room on the first floor.
He made a table, TV, sofa, room light, window, and steps.
This is the second floor.
There are some books in the bookshelf.
My son wrote their titles on each book.
There is a wash room behind the door.
The picture of a flower is hung on the wall.
He was absorbed in making this for a while.
I was really impressed with his detailed work and creativity.
Your son has a lot of attention to detail. I would not have the patience.
Here is a list of some of the other issues found with the rest of the post:
My 7-year-old son made a small house using a cardboard last Tuesday.
My 7-year-old son made a small house using some cardboard last Tuesday.
Reason: Changed a cardboard to "some cardboard" you could also remove the word "a" entirely.