Children should learn to be honest from a young age.
Tips
usage
诚实 describes a personal quality (being honest), while 诚信 is more about trustworthiness as a principle. 说老实话 (shuō lǎoshi huà) is a colloquial way to say 'to be honest'.
mistakes
Don't confuse 诚实 (chéngshí, honest — an adjective) with 老实 (lǎoshi, honest but also naive/simple). 老实 can imply someone is too gullible.
