
Questions & Answers about atai ga takai.
値 means something like price, value, or worth, depending on context.
That means this sentence can describe:
- a high price
- a high market value
- high worth
Japanese often leaves the exact nuance to the situation. If you are talking about buying something, it may feel like the price is high. If you are talking about worth or merit, it may feel more like the value is high.
が marks 値 as the thing that has the property 高い.
So the structure is basically:
値 = the price/value
が = subject marker
高い = is high
This is a very normal pattern in Japanese: noun + が + adjective.
If you changed it to は, you would be making 値 the topic instead. That can sound more contrastive or like you are specifically commenting on the price/value as opposed to something else.