Activity
Varsity Tutors

Varsity Tutors: Hotmath: Sequences and Series

For Students 9th - 10th Standards
Hotmath provides 20 practice problems relating to sequences and series. Each of the practice problems include a step-by-step guide for solving.
Interactive
National Council of Teachers of Mathematics

Nctm: Illuminations: Limits

For Students 9th - 10th Standards
In this activity, you can see a representation of several geometric series and their limits.