Attached image of a spot and cross
Cover your right eye and hold the spot and cross image at arm’s length, with your nose centred between the spot and the cross.
Stare at the cross, then slowly move the paper towards you.
Keep staring at the cross; keep your nose centred.
When the paper is 20-30cm away from your face, the spot disappears, as the spot is over the blind spot of your left eye.
This is a tricky activity - keep trying.
Hard for Ks and some grade 1s.