20 CFR § 404.367 - When you are a “full-time elementary or secondary school student”.
You may be eligible for child's benefits if you are a full-time elementary or secondary school student. For the purposes of determining whether the conditions of entitlement are met throughout the first month as stated in § 404.352(a)(2)(i), if you are entitled as a student on the basis of attendance at an elementary or secondary school, you will be considered to be in full-time attendance for a month during any part of which you are in full-time attendance. You are a full-time elementary or secondary school student if you meet all the following conditions:
(a) You attend a school which provides elementary or secondary education as determined under the law of the State or other jurisdiction in which it is located. Participation in the following programs also meets the requirements of this paragraph:
(2) You are in an independent study elementary or secondary education program in accordance with the law of the State or other jurisdiction in which you reside which is administered by the local school or school district/jurisdiction.
(b) You are in full-time attendance in a day or evening noncorrespondence course of at least 13 weeks duration and you are carrying a subject load which is considered full-time for day students under the institution's standards and practices. If you are in a home schooling program as described in paragraph (a)(1) of this section, you must be carrying a subject load which is considered full-time for day students under standards and practices set by the State or other jurisdiction in which you reside;
(c) To be considered in full-time attendance, your scheduled attendance must be at the rate of at least 20 hours per week unless one of the exceptions in paragraphs (c) (1) and (2) of this section applies. If you are in an independent study program as described in paragraph (a)(2) of this section, your number of hours spent in school attendance are determined by combining the number of hours of attendance at a school facility with the agreed upon number of hours spent in independent study. You may still be considered in full-time attendance if your scheduled rate of attendance is below 20 hours per week if we find that:
(1) The school attended does not schedule at least 20 hours per week and going to that particular school is your only reasonable alternative; or
(2) Your medical condition prevents you from having scheduled attendance of at least 20 hours per week. To prove that your medical condition prevents you from scheduling 20 hours per week, we may request that you provide appropriate medical evidence or a statement from the school.
(e) You are in grade 12 or below; and