Something I started this semester in order to have better quality time with Niko was an informal preschool curriculum. Most weeks (depending on how busy we are with other things) we learn a new letter, number and shape/color, and often learn a new word like "calf" or "lighthouse." I haven't been terribly consistent about it, but it has definitely been fun coming up with little projects to do together to introduce Niko to letters and numbers.
Here's some snapshots of a project we did a few weeks ago:
(Niko glued all these squares down by himself!)
By no means does Nikolai know all of the letters and numbers we've done by heart, but that's not really the point for me at this stage of the game. Mostly, it's been fun to engage him in small, crafty projects that we both enjoy doing :)