"Ability groups" refers to dividing or grouping students based on their skills and capabilities. It is done to provide them with suitable instruction and activities that match their level of understanding and learning abilities. Full definition
The children were put into mixed ability groups of 3/4 (depending on the amount of questions provided for each planet). (tes.com)
It gradually removes the support given through the questions but it was made with my very low ability groups in mind. (tes.com)
In addition, the practice of ability grouping for guided reading within the regular education classroom further supports this aspect of instruction. (ciera.org)