Gifted math students are often able to solve problems in their head without showing much, if any, work on paper. In fact, especially younger students, cannot showing their work. Because they already know the answer, it's like they have to work the problem backwards to show their work.
The purpose for showing work is to learn the process correctly. With continual practice, fluency or automation develops and over time, some of the steps are dropped because you "automatically" do them in your head. This is especially important on standardized tests where speed and accuracy are required. So, we don't want to frustrate a student by making them show every step when the end goal is to at least do some of it in your head.
If you have a gifted math student who really "gets math", is in 6th - 8th grade, working at least one grade level ahead, do not require them to show their work on homework problems (Practice Sets). However, if they get the problem wrong, they should follow the Corrections steps to re-learn and correct missed problems, including working the problem correctly on their correction notes.
To start developing this skill of showing work, have the student show their work on the quizzes. There are only four questions on the quizzes so this should not be overwhelming or frustrating.