These addition mats work best in small group learning experiences where students are learning about adding with a number line. Each student in the group is given an addition mat. Students place a random or specific number (teacher choice) of fish into their two fish tanks. Students then write how many fish are in each individual tank in the small box. Students then use the number line to determine how many fish they have altogether. The answer is written in the large box on the right hand side. If students are using this activity individually there is a black and white printable recording sheet for ten sums that can be filled in and given to the teacher. Includes – Fish Tank Addition Mat with number line, small fish cards, black and white printable recording sheet and instructions for use.