It is possible that your son is gifted in math. You may want to discuss this with his preschool teacher. If that's the case, it is an ability that can be developed to the child's advantage, rather than treated as a problem. Note that gifted kids are often bored by tasks that do not challenge their abilities. So when your son is diverting his attention, the root cause may include a gift in something, not just a deficiency in focus.
Compare your child's math abilities and interest in numbers to that of his peers (for your own guidance). For example, according to the CDC, the milestones for 4 year olds include these, which suggests that your son is ahead of most peers:
Names some colors and some numbers.
Understands the idea of counting.
(https://www.cdc.gov/ncbddd/actearly/pdf/checklists/all_checklists.pdf)
How to keep the child focussed on the job? I recommend reading about and discussing with your son's teacher and/or pediatrician teaching self-control. This is an active area of research. See, for example, this post:
Gwen Dewar: Teaching self-control: Evidence-based tips:
https://www.parentingscience.com/teaching-self-control.html
In brief:
- Remove the distractions. If the child needs to focus on singing, have him face away from the clock with the numbers that he finds distracting.
- Reward self-control. Praise the child consistently when he keeps focussed on the task. Praise is usually more effective than punishment.
- Play games that teach self-control. For example, "Red light, Green light", "Simon Says", "The Freeze Game", especially with reversing the clues.
MORE DETAILS:
Play games that help preschoolers practice self-control
The game sessions featured the modified version of “Red Light, Green
Light” and other games designed to give kids a self-regulation
workout:
The Freeze game. Kids dance when the music plays and freeze when it
stops. Dance quickly for fast-tempo songs, slowly for slow-tempo
songs. And then reverse the cues: Fast music = slow dancing. Slow
music = fast dancing.
Color-matching freeze. In this variant of the
freeze game, kids don’t just stop dancing when the music stops. First,
they find a colored mat and stand on it. Then, before they freeze,
they perform a special dance step. There are several,
differently-colored mats on the floor, and each color is linked with a
different dance step.
Conducting an orchestra. Kids play musical
instruments (like maracas and bells) whenever an adult waves her
baton, increasing their tempo when the baton moves quickly and
reducing their tempo when the baton slows down. Then the opposite
rules apply (e.g., kids play faster when the baton moves slowly).
Drum beats. A teacher tells kids to respond to different drum cues with
specific body movements. For example, kids might hop when they hear a
fast drum beat and crawl when they hear a slow drum beat. After a
time, kids are asked to reverse the cues.
The kids played these games
twice weekly is sessions of thirty minutes each, and after eight
weeks, the researchers re-assessed the children's self-regulation
abilities. Kids who began the program with above-average self-control
showed no improvements, but the story was different for children who
had been struggling. Preschoolers who started with low self-regulation
scores (below the 50th percentile) had gotten better.
RELATED:
At what age should a child be able to count to 10?
Kid genius help