My 4 year old daughter sometimes has a little trouble to blow strong enough that the projections come indeed as pens, some go very well, others a little less. The ink does not wash well, after several intensive washing, the hands are very colorful! (Not yet had but a little fear there are projections on clothes ...)
Apart from these 2 points, my daughter like this kit, it changes the traditional patterns and results with stencils are bluffing,
