Jacob's Math Training Jacob's Math Training is an adaptive application helping pupils to improve their arithmetic skills. It also helps teachers to follow-up their pupils' work. You will be buying a key that works for ... Cost: $27.5 Buy full version       Trial version           Descriptions Jacob's Math Training: Jacob's Math Training is an adaptive application helping pupils to improve their arithmetic skills. It also helps teachers to follow-up their pupils' work. You will be buying a key that works for Jacob's Math Training v2.5 or v2.6. The price varies depending on the number of installations you intend to unlock.