Zoe needs to back up her music collection, but do her friends have enough space on their computers to help? Find out as you teach your class how to add two- and three-digit numbers with regrouping. Place value is emphasized as both the...

Have some fun building squares out of triangles. Pupils investigate the partial sums of odd numbers. Using the sum of the first four odd numbers, learners see that it can be rewritten as a sum containing a triangular number. Simplifying...

Help your class develop an understanding of sigma notation. Pupils match the sigma notation with the sums. Using the expanded sums, learners evaluate the summations. The scholars move on to prove a property of sums.

Sum up the shortcuts. The interactive allows pupils to discover a shortcut in finding a partial sum of an arithmetic series. Learners use the shortcut to find other sums and to verify the process.