There are several synonyms for the phrase "not amount to much/a great deal" that can be used to convey a similar meaning. Some options include "insignificant," "meager," "trivial," "negligible," "paltry," and "inconsequential." Each of these words suggests that something has little value or importance, and does not hold much weight in the bigger scheme of things. They can be used in a variety of contexts, such as describing a small amount of money or a minor achievement. When looking for ways to express the idea that something is not particularly significant or impressive, these synonyms can come in handy.