You can build up tech points by paying constant attention to the village and having your kids pick up every single collectible item (this also helps with the food situation, of course). Once a new item is found, every duplicate of that item accumulates tech points. Some are worth more than others. In one village I managed to keep everyone well supplied with food for several hours, just collecting mushrooms, and meanwhile the kids accumulated over 3,000 tech points with collectibles in 1 hour of play.

Also, put as many of your villagers at the research table as you can. Don't worry about achieving master/elder status until your village is well established and secure for food.

Hope that helps, good luck, and enjoy.