To view and enter a Series Challenge, tap on the House icon at the bottom of your screen to access the Main Challenges page.

Series Challenges will say "Series" at the top left corner of the thumbnail. The thumbnail also includes a progress bar where you can track how many Challenges you have entered for a Series.

Tapping on the “Enter The Series Challenges” bar in pink at the bottom of the Main Challenges page will also bring you to the next Series Challenge.