§ 61.215 Ground instructor privileges.
(a) A person who holds a basic ground instructor rating is authorized to provide—
(1) Ground training in the aeronautical knowledge areas required for the issuance of a sport pilot certificate, recreational pilot certificate, private pilot certificate, or associated ratings under this part;
(2) Ground training required for a sport pilot, recreational pilot, and private pilot flight review; and
(3) A recommendation for a knowledge test required for the issuance of a sport pilot certificate, recreational pilot certificate, or private pilot certificate under this part.
(b) A person who holds an advanced ground instructor rating is authorized to provide:
(1) Ground training in the aeronautical knowledge areas required for the issuance of any certificate or rating under this part;
(2) Ground training required for any flight review; and
(3) A recommendation for a knowledge test required for the issuance of any certificate under this part.
(c) A person who holds an instrument ground instructor rating is authorized to provide:
(1) Ground training in the aeronautical knowledge areas required for the issuance of an instrument rating under this part;
(2) Ground training required for an instrument proficiency check; and
(3) A recommendation for a knowledge test required for the issuance of an instrument rating under this part.
(d) A person who holds a ground instructor certificate is authorized, within the limitations of the ratings on the ground instructor certificate, to endorse the logbook or other training record of a person to whom the holder has provided the training or recommendation specified in paragraphs (a) through (c) of this section.
***
Yes, you can charge for your time.