Insert-everywhere function
Check this Stack Overflow question out, which has a solution to the same problem. A simplified version would look like this

(define (insert-at pos elmt lst)
 (if (empty? lst) (list elmt)
 (if (= 1 pos)
  (cons elmt lst)
  (cons (first lst) 
        (insert-at (- pos 1) elmt (rest lst))))))

(define (insert-everywhere sym los)
  (map (lambda (i)
         (insert-at i sym los)
           )
       (range 1 (+ 2 (length los)))))



There is a function written for inserting at a particular position.
Then we have our iterative function that maps over the elements in the list. 


Alternatively, there is the recursive solution found in the link above. It does this by using conditions and cons (which appends to lists together). It seams a bit clunky, but map really cleans it up.