What should DC do with £20000

[MissJimmysjumpers]

DCis 17 and is about to receive a gift from extended family that is meant to give them a financial cushion as they become independent. Given that they have no pressing need for it, what would you suggest they could do with it for next few years ?
Dc is likely heading to uni but those costs will be supported within their family.

Simply a cash ISA. Instant access and reasonable return without any risks. If they may need it within a few years, I'd be reluctant to invest it.

Cash isa.
National savings certificates (but less accessible)
Premium bonds (never know might win big)

I'd suggest they lock most of it away in something that needs a wait to withdraw, to reduce the temptation to fritter. A fixed term or notice account.

I'd keep thr majority available for short-to-medium term needs rather than investing, but it might be worth putting just a bit - 10% perhaps - into a pension so they've made a start. Even a small amount at this age will make a big difference by retirement.

Diversify for safety but go for slightly riskier funds as she is so young and set and forget the following on a low fee platform that easy to navigate.

S & S ISA 5K
Premium bond account 5k
4 k LISA (plus 1k from government)
SIPP 5k (plus about 1k form government , not sure what current contribution is)
1K instant access cash isa

In one year she will have grown it to over 23k fairly easily

I am not a financial expert at all but this is what i am doing for my kids when they are old enough and their Junior ISAS need to be changed.