The Arthur Waser Foundation supports capable and committed Montessori teachers through challenge funds, which are used to finance new model Montessori kindergartens as well as renovation and expansion works for existing Montessori kindergartens. Following the principle of challenge funds, AWF generously matches the funds raised by the Montessori teachers so teachers are encouraged to raise part of the funds required for their projects themselves. In addition to this, AWF finances a large number of vouchers for Montessori refresher courses, which are held at the Montessori teacher training centers. During kindergarten visits, zonal coordinators working for the national association of Montessori teachers («Montessori Community of Tanzania») hand out these vouchers to Montessori teachers in need of a refresher course. The teachers then complete two-week courses at the nearest training center during which they refresh their theoretical knowledge and repair their Montessori teaching materials.