Where is game 16 (in the videos)?
Where is the actual game (there's no car!) in the pseudo 3D car racing game?
This stuff will be quite useful for people looking to get one of these games running by typing it in theirselves or maybe if they're stuck somewhere and might find the answer in your code so nice of you to share this.
One of the first things I noticed, which was in the first video, was something like:
float time = clock.getElapsedTime().asSeconds();
clock.restart();
timer += time;
This could be just:
timer += clock.restart().asSeconds();
I don't want to comment too harshly as it's nice that you did it so I'll leave critiquing the code to others (who obviously know more about it than I do).