Piano is recommended~because the piano can be performed in public places, which will cultivate the child's social skills in the future, and also allow more people to understand him and make connections accordingly.
Although calligraphy has improved your self-cultivation, what can be reflected is that others will praise your handwriting.
If a child wants to learn model aircraft, it can cultivate his hands-on ability. After school time, it is better to let the child see what he is interested in. Do not stop his interest at an early age, which is not good for the child's development