I am unable to get the language to change on these few things under course overview. Does anyone know what I am doing wrong?
Is it a core or contributed block?
When you have editing on, what type of block does it say it is? Or what is the 'block_' class when you inspect the markup with browser development tools?
This is how it looks. the block class is this - block block_myoverview
Ok, that does appear to be the course overview block, however not the same block that you've shown in the original post. That area is a 'content' block region and can contain many blocks, so what is the name of the block with the problem please?
These strings are correctly in the en language file of the myoverview block
However, it is possible they have not yet been translated into the es International Spanish language pack you are using.
This appears to be a language translation issue, rather than a courses or even myoverview block issue.