This lesson plan is for a 40-minute class for 9-10 year olds on numbers up to 100. It includes a warm-up reviewing previously learned numbers through a song. Students are then split into two groups and participate in two activities - a numbers matrix puzzle and a question game involving math problems - designed to reinforce numbers up to 100 while developing cooperation skills. The goal is for students to identify and use numbers up to 100, follow instructions, and work cooperatively in groups.