I don't know what your taps are like, but replacing them with thermostatic ones is normally not that expensive and you'll have years of benefits from them. They are the way to make your taps safer, so I would really consider saving up for at least the bath/shower tap.
The ones available in the Netherlands (and presumably all over the world) have a button-lock to prevent accidentally setting the temperature above 38 C. This will prevent little accidents (especially in the shower) long after your children understand that the hot water is dangerous. Try these out when selecting one, as some models are too easy to unlock when just grabbing and rotating the knob.
The luxury models also prevent the metal of the tap itself from getting hot by having the cold water flow under the surface of the tap. This is for those occasions when your children grab the tap to keep their balance or get up out of a bath.