La Casa Gratuita
Though the text on the reverse claims that these have value (ES DINERO) they are not paper money so are only mentioned because they (currently) appear in catalogues.
These coupons were to be collected and $50 worth entitled the holder to one ticket in a lottery of/for the Casa Gratuita (Free House). The wining number would be the same as that for the major prize in the National Lottery.
Maz Lehmann registered the design and copyright to these coupons with the Secretaría de Educación Pública on 19 June 1923Diario Oficial, 10 July 1923 .