It varies from subject to subject,
but most students will mainly write notes for ''Students Learn About'' in a subject like Economics or Business Studies for example.
Then, the content from ''Students Learn About'' can be then used to answer quite a few of the ''Students Learn To'' dot-points essentially and some ''Learn To'' dot-points are skills such as calculations.
I've seen some students write notes for the ''Learn To'' section (probably not all of the dot-points but some of them) but it's mainly ''learn about'' that you'll have notes for.
Technically, both can be tested but you'll find that the ''Learn To'' section is very important when it comes to exam questions --> in Business Studies for example, they could always take out a ''Learn To'' dot-point then change a word or two and BAMMM - that's an essay question or possibly a short answer question in the exam.
Skills questions (which appear in short answers) come from the ''Learn To'' section as welll.