First of all, as someone noted already, lots of people score high. Search, and you'll find that 1% of the under 18 people score 162. The complete article says that 2 schoolgirls, both indian born, scored 162 in the same test took by more than 200 people (a whole school), which is within statistics and nothing exceptional:
London schoolgirls score higher IQ than Einstein and Hawking | Education News | News | The Independent
Top Mensa score has girls ?buzzing?
Here, indian journalists spread this info in India as motivational nationalist propaganda, because these was 2 indian born girls. Some been so sly to talk of 1 girl only, because 2 girls was letting guess this is just 1 every 100 kids, so million kids score 162. The fact that Einstein is "believed" to score 160, simply shows that such test had nothing to do with Einstein, which is not 1% occurring, but 1 every several million. Example of indian TV inteview below:
If you search even better, you see the whole story is that the school of these 2 girls, full of indian and pakistani natives, had 56 kids enter mensa (2% of people normally):
School gets record number into Mensa - BBC News
Here you read: "Since 2011, Mensa has tested 7,476 pupils through the schools programme and 2,026 have been invited to join as a result. That means around 27% of candidates put forward have been invited to join the society. Around half of adults who apply to join Mensa get in.".
Now I wonder, if there are 100 times more MENSA members than normal scientists, how anyone serious can claim a mensa membership has anything to do (comparing with) exceptional scientist as Einstein?
In fact, many pass the MENSA online tests (much like 27% of the kids of the london school, nothing exceptional), but they don't join the club since they are smarter than those boosting MENSA certificate, I know a few and I can tell some are idiots (suggestion for MENSA: there should be also a banning procedure... yes you do have idiots who passed test and boost MENSA certification).
PS: Let me be evil, but, solving mensa test is a specific skill you can train, like solving riddle and puzzles. I mean, you can train kids for months in solving riddles similar to the mensa ones, perhaps with the free or past tests online or in cell phones, that could be a secret strategy of that one school, in order to boost the number of students that pass the mensa test.