I can only speak from ds1. When he started reception he could read a little, and could write his name.
Reception
Learned to read fluently, learned to write, including letter formation and building words up phonetically (i.e. working out spellings himself).
Project work on various topics - eg mini beasts, including some literacy, some science, some dance etc etc
Plus lots of play, socialising
Yr1
Continuation of reading, writing.
Maths - learning times tables, telling the time, manipulation of bigger numbers (35-10, 17+8), they were doing about friction and pulleys this week
Spanish, lots of singing, more project work (sea, homes etc), lots about their community and the international community
Obviously lots more as well - Yr1 did seem to be a big step change away from the play based reception.