A more challenging extension to this could be to get them to add a second sprite. This, I believe, involves moving the students further in their computational thinking.
By now, the students have made a good deal of progress and have had plenty of practice using Scratch. They are felling pretty confident!
They have also learnt that it is possible to have two things happening at the same time. and have some experience of coordinating these things.
It's time to introduce a new concept in the next lesson. I like to tell them what's coming up next, maybe even give them a sneak preview. Telling them what comes next keeps their interest high and means that they are looking forward to the next lesson.So they usually get pretty excited when I say they are going to animating characters.
And, of course, they will be learning another important concept of computer programming: iteration (looping).