Keep your "expectations" age appropriate with development in mind.
KNOW what a 16 month old, is developmentally.
At this age and through at least 2+ years old, a baby does NOT "play" interactively like older kids. They "parallel play". Look this up online.
At this age they explore. That is how they learn.
If expectations are not in line with a child per their age and development, then 3 things happens:
1) the parent gets frustrated
2) the child gets frustrated.
3) there are then "problems".... which the parent feels the child is. But ultimately, the child is just being their age. Which is not congruent with what the parent wants or expects...
Gymboree classes are REAL great... try seeing if there is one in your area.
Here is the link:
http://www.gymboreeclasses.com/index.jsp
These classes are age appropriate... and they learn a lot, via "play."
Your baby, is not a full Toddler yet. You cannot fast forward her 'ability' to 'behave' or participate in a group activity... and they don't yet even have 'emotions' fully developed yet nor social ability....
AND... make sure that activities in a group is NOT at a nap time... or the child will not be at her best, and will get over stimulated. Not good timing.
Sure, kids this age are getting 'independent.' That is normal.
Just let her explore... she does NOT yet have to follow directions... just let her explore. THAT is how they learn about their world.
Kids this age are also very reactionary... still. It is how they are. Kids this age do NOT have any "impulse control" nor is it fully developed yet. It will not be fully developed yet until at least 4-5 years old.
And yes, group size is also a difference. Too many kids= too many over stimulation... and some kids just do not handle that well yet. Per their age. Smaller groups, are generally more well suited. Normal.
Your baby is fine.
That is how they develop.
Activities are good... but each child reacts differently.
A good book is: "What To Expect, The Toddler Years."
Story time... is for older kids.
all the best,
Susan