Is it possible to use `provide` in Racket's Student Language?

Question

2.rkt has the following definition:

(provide plus)

(define (plus a b)
  (+ a b))

and 1.rkt has:

(require "2.rkt")

(plus 3 4)

Both are in "Beginning Student Language" level (so no #lang line required) and are in the same directory.

This leads to a provide: this function is not defined error in 2.rkt.

Adding (require racket/base) in 2.rkt fixes this but then I can do things like (cons 1 2) which shouldn't be allowed in BSL.

How can I use plus in 1.rkt in BSL?