Since well-endowed universities seem to do so much better than the broader market, and since cost of attending university (in the US) seems to grow so much fast

Since well-endowed universities seem to do so much better than the broader market, and since cost of attending university (in the US) seems to grow so much faster than broader inflation, I was imagining an interesting product the other day to take advantage of this. Imagine if universities sold an investment product that guaranteed a small, market-linked return (indexed, or inflation-linked, or whatever), with the additional feature that the product could instead be exchanged for tuition credits in the future at an alternate rate linked to the growth in tuition cost at that college. The intention is that a parent who thinks their child may attend that school can reasonably by "future tuition credits" with zero or low cost compared to other investment of those funds even if realizing the risk of their child attending a different/no university; the child can attend at least one university at a reduced and hopefully more manageable rate; and the university can increase their endowment both with the float, and by keeping the difference between their historically better returns than the guaranteed rate. Does this make sense as a financial product?