Kant- synthetic a priori Dotto

For something to be analytic instead of synthetic is must be a priori knowledge, a general truth prior to an observation of it. I don't buy into Kant's "breakthrough" of synthetic a priori knowledge. Surely his logic is close but in order for someone to understand math, they must first grasp the concepts. Numbers are taught and learned so to overlook that we do not grasp numbers independent of observation is ridiculous.