It is generally not appropriate to allocate learning objectives to every lesson within a unit, since that implies that learning can occur and be evaluated within single lessons. This is very much at odds with current understanding in cognitive psychology.
Instead, teachers are expected to consider their teaching at the unit level, and introduce and reintroduce inquiry questions, AtLs and other IB specific elements, as and when they deem them appropriate. Learning objectives can also be used, but there is no expectation in terms of format or frequency.
More information coming soon on this topic.