Well, if you did, please let me know so I can have the administrators reverse is, I mean if you are satisfied with the answer I am about to give and I believe you will be. Go back to them and tell them that they are incorrect to deny the student to study in high school. Take a look at this OFFICIAL chart form Immigration and Customs Enforcement (ICE):
As you see, the child can study. They even give you the section of the law: 8 CFR 214.2(f)(15) Specifically:
Spouse and children of F-1 student. The F-2 spouse and minor children of an F-1 student shall each be issued an individual SEVIS Form I-20 in accordance with the provisions of §214.3(k).
(i) Employment. The F-2 spouse and children of an F-1 student may not accept employment.
(A) F-2 post-secondary/vocational study.
(1) Authorized Study at SEVP-Certified Schools. An F-2 spouse or F-2 child may enroll in less than a full course of study, as defined in 8 CFR 214.2(f)(6)(i)(A)-(D) and 8 CFR214.2(m)(9)(i)-(iv), in any course of study described in paragraphs (f)(6)(i)(A) through (D) or (m)(9)(i) through (iv) of this section at an SEVP-certified school. Notwithstanding paragraphs (f)(6)(i)(B) and (m)(9)(i) of this section, study at an undergraduate college or university or at a community college or junior college is not a full course of study solely because the F-2 nonimmigrant is engaging in a lesser course load to complete a course of study during the current term. An F-2 spouse or F-2 child enrolled in less than a full course of study is not eligible to engage in employment pursuant to paragraphs (f)(9) and (10) of this section or pursuant to paragraph (m)(14) of this section.
(2) Full Course of Study. Subject to paragraphs (f)(15)(ii)(B) and (18) of this section, an F-2 spouse and child may engage in a full course of study only by applying for and obtaining a change of status to F-1, M-1 or J-1 nonimmigrant status, as appropriate, before beginning a full course of study. An F-2 spouse and child may engage in study that is avocational or recreational in nature, up to and including on a full-time basis.
(B) F-2 elementary or secondary study. An F-2 child may engage in full-time study, including any full course of study, in any elementary or secondary school (kindergarten through twelfth grade).
(C) An F-2 spouse and child violates his or her nonimmigrant status by enrolling in any study except as provided in paragraph (f)(15)(ii)(A) or (B) of this section.
So let them know they are wrong and to enroll your nephew, post haste!
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