You can make a small tasbih (Muslim rosary) with your child. Let him/her to paint the beads and string on the rope. We used different types of macaroni for this tasbih. There are 33 beads here. You can paint them 11 beads in one colour, 11 beads in different colour and 11 beads are in another colour. So your child can easily distinguish dhikr "Subhan'Allah, Alhamdulillah, Allah u Akbar" and say 11 times each after performing salah.