A mathematical model is proposed to measure the learning curve in the California Verbal Learning Test-Children's Version. The model is based on the first-order system transfer function in the form Y = B3*exp[-B2*(X-1)]+B4*{1-exp[-B2*(X-1)]}, where X is the trial number, Y is the number of recalled correct words, B2 is the learning rate, B3 is interpreted as readiness to learn and B4 as the ability to learn. Children's readiness to learn and ability to learn were lower than adults. Modeling revealed that girls had greater readiness to learn and ability to learn than boys.