A bit much If something is excessive or annoying, it is a bit much.
A day late and a dollar short (USA) If something is a day late and a dollar short, it is too little, too late.
A fool and his money are soon parted This idiom means that people who aren't careful with their money spend it quickly. 'A fool and his money are easily parted' is an alternative form of the idiom.
A fool at 40 is a fool forever If someone hasn't matured by the time they reach forty, they never will.
A little bird told me If someone doesn't want to say where they got some information from, they can say that a little bird told them.
A little learning is a dangerous thing A small amount of knowledge can cause people to think they are more expert than they really are.eg. he said he'd done a course on home electrics, but when he tried to mend my table lamp, he fused all the lights! I think a little learning is a dangerous thing
A lost ball in the high weeds A lost ball in the high weeds is someone who does not know what they are doing, where they are or how to do something.
A OK If things are A OK, they are absolutely fine.
A penny for your thoughts This idiom is used as a way of asking someone what they are thinking about.
A penny saved is a penny earned This means that we shouldn't spend or waste money, but try to save it.
A picture is worth a thousand words A picture can often get a message across much better than the best verbal description.
A poor man's something Something or someone that can be compared to something or someone else, but is not as good is a poor man's version; a writer who uses lots of puns but isn't very funny would be a poor man's Oscar Wilde.