It is very difficult for a child to focus on anything for more than a few minutes as they have high curiosity levels. To increase the concentration level of a child, below are the few tips-
1. Give them a reward
Whenever they complete any task on a given time give them a small reward as it will give them happiness in completing any work. Don't give them bigger gifts as it will make them greedy.
2. Mix pleasure with work
Give them small breaks in between work to play. They can refresh their mind and can concentrate better
3. Divide bigger task into smaller ones
If they have so much of homework or any other task, divide it into smaller ones as smaller projects need less time to complete
4. Give them games which need focus
Get them games in which they need to focus. Due to this, they will learn to sit for longer time and can concentrate better