We ventured into the Central Market once and I vowed never to return. The market has historical merrit, being teh oldest running market in the US, but the history is crowded out...literally. It is very very cramped, loud and hot in there. The isles are tiny. You would really struggle trying to use even a small stroller and it is very ahrd keeping track of children walking next to you. The prices are also high for a Farmer's Market, probably due to this Market being very touristy.
If you are willing to go slightly off the beaten path I would recommend the Roots market about a 15 minute drive west of the Central Market. There you will get great prices, buy directly from Amish farmers and have much more room to move around, since it is both indoors and outdoors.
Next to the Heritage Center, breathe in the delicious smells of Amish baked goods coming from the Central Market, the site of which has been operating as a farmers’ market since the 1730s.
We stopped in to visit the central market when we were in Lancaster for some picnic supplies. The kids enjoyed walking around seeing some local handicrafts (and begging for us to buy them) and baked goods. A good number of stalls were run by local Quakers, which included their handmade items and food. The kids enjoyed trying different things. We had a fantastic picnic spread when we left the market.