A search for F* Windman turned up only two results: a boy and a girl, so Fajga had to be the student who signed the album. In addition, her birthday made her the right age to have attended School #8B.
I matched Fela to her family by comparing addresses. Fela lived at Holz 13 18 and Kilin 89 before moving on January 20, 1942, to Holz 21 39. Other family members that matched this pattern of addresses includes her mother, Rajzla (b. 1890), and siblings Ita (b. 1919) and Chawa (b. 1921).
Fajga died, presumably in the Ghetto, of currently unknown causes on November 15, 1942. Like Fajga, Chawa died in the Ghetto on February 19, 1942, of (according to hospital records) pulmonary tuberculosis. Both Rajzla and Ita were deported on September 11, 1942, on which date there was a deportation to Chelmno.