Question

How to raise IQ of ppl around You?​

Answer 1

The average rate of increase seems to be about three IQ points per decade in the United States, as scaled by the Wechsler tests.

Answer 2

your IQ can change over time. But [IQ] tests give you the same answer to a very substantial extent, even over a period of year. The older you are, the more stable your test score will be.

The most volatility in IQ scores is in childhood, mostly in adolescence. Offhand I can't think of a reason why it would be, it just seems to be the case.