I considered this also (putting money into high interest account and paying it off on graduation), but when we looked into it (Feb 2023), the interest rate (RPI) was 13.5 per cent ( but it has gone down a bit now), and high interest accounts are nowhere near that. And what with compound interest / not making any loan repayments during the degree, I worked out that (assuming RPI stayed the same, at 13.5 per cent (which it prob wouldn’t)), four consecutive years of borrowing approx £14k student loan (so a base borrowing of £56k for an integrated MSc), would become a loan of around £70k at graduation, with the compound interest at such a high rate.
So while the interest rate is likely to be on average lower than 13.5 per cent, we felt it was worth paying it as we go. In reality, some of our costs have gone down since dc1 has gone to uni in Sept (food bills, energy bills, weekly music lessons, driving lessons, pocket money, mobile phone bill etc etc) which means that the additional ongoing cost to us works out much less than the headline cost of the tuition and catered accommodation, plus extras.
To avoid eating away too much of our savings, we are just shifting what we spend (and on what) slightly. So, we have an old car which looks scruffy, but it still works and is economical to run, so we will not replace it until it actually dies. I am cutting back on household spending (switching from Sainsburys and the local M&S) to mainly Lidl / Iceland (and just getting a couple of special bits in sainsburys). Our last holiday we took (in UK), was a choice between 2 cottages - we went for the one that was 2/3 the cost of the other, in a different area, but still really lovely. I try to keep in my head the target amount each term that I am trying to save. It is so much more palatable doing it this way, in small chunks, than considering the whole amount. And actually calculating what your savings are now that they are not living with you also really helps (eg for context I worked out we were around £500 better off without dc1 living with us. So this ‘saving’ is now put towards the uni accommodation costs.
I understand that we are very very fortunate to be able to do this, and that the majority of people would not be able to do this, and would have to rely on student loans. But it is something we wanted to do for our dc. As a family with 3 children, we couldn’t have afforded to send them all to private school (so it’s state schools for all 3) but they are staggered in age enough so that this approach is manageable for us.