Targeted at kids this educational anime does a fairly good job. There is always a thin line in educational anime between being interesting and becoming boring, but in Pikaia they were able to balance out the entertainment and educational parts.
The story is pretty interesting, it often felt like being a fusion of futuristic elements, but also the past of Cambrian era. Mostly the pacing of the show was rater slow, except for their little but important adventure missions.
There was usually at first a block with the actual pikaia episode (short recap & current episode) and after that the educational explanation block, in which they
referred to the episode, the history/background behind it, but also to today's technology and research. In pikaia they were able to pique the interest from the episode for the follow-up educational part. After this, there always followed another short sequence (with simpler animation) in which the animated singers elfin' had a little platform to talk about the episode or the educational part.
As I don't like such little short "talkshow-ish" sequences that much at the end of animations, I think it might have been great for the music cast to present themselves as well, so I don't mind that much anymore.
Overall the music was really good, the opening suits the anime well, but also the background music was always well chosen. Good job on that!
The animation quality was also on a good level and quite enjoyable.
What I probably liked the most was the character design and the series composition of this series. It has been thought through and written loveable.
The short anime episodes (about 15 minutes long) were a good choice as it stays easy digestible and relaxing to watch. I can imagine to watch this series after a stressed day after work/school. Don't expect deep hidden secrets, which have to be discovered by yourself, it is a series aimed at kids after all. Well done NHK!