Ideas for best return over 4 years?

[Puffincrossing]

My older dc starts their GCSEs this September which has made me think about what happens next and how I really should have been thinking about university costs. I know I'm far too late thinking about this so no one needs to tell me how stupid I've been. However, I've looked at mse to get a guide as to how much I need and it's a lot! It won't be impossible but is going to require a substantial life style shift for something that may not even happen and at a time when all costs are increasing. I have 4 years to invest my money, where's the best place to put it? Locking away tends to pay more but as interest rates are going up I wonder if I'll end up locking into a low rate.

I’m not sure in what sense you are using the word invest because you seem to be using it to mean savings rather than investing in the stocks and shares market. If you are talking about investing as in investing in stocks and shares I would have to say that for years is quite a short time span and would perhaps not give you enough time to write out any market difficulties if they occur at the end of the period when you need the money. Particularly so if you are new to investing. If you are speaking of saving then of course anything you can save will help and locking away is usually not possible unless you have a lump sum because most drip in savers or not the fixed-rate bonds. There will be exceptions. I would suggest you read up Martin Lewises website section on the savings guide and look at which savings accounts might suit you. You may find that many savings accounts of a decent interest rates of up to even 5% for the first year after which you might need to keep moving your savings to benefit from similar rates at different places.