Small tasks will keep kids fairly busy -- but notable advancement in the game doesn't happen very fast. Kids can earn money fairly easily through a variety of tasks in Supermarket Village - Farm Town, such as completing orders, so they should be able to purchase buildings when prompted. Constructing them will take some time -- like many things in the game, it involves a wait. Upgrades, though, can be another story. Because your warehouse gets full fairly easily, expanding it is key. You otherwise may try to harvest crops and find there's nowhere to put them, which can slow or halt the availability of feed, in turn stopping cows from producing milk, and may affect other actions, eventually impacting product availability and profits.
You need to have tools on hand, such as a hammer -- sometimes more than one -- to make building upgrades. Those items cost a hefty amount of gems, though, which can be hard to come by. Kids may find they're short on them before the tutorial is even over. They may be able to get some tools another random way, such as by successfully playing one of the mini-games that occasionally pop up -- including a pinball challenge where you shoot a hamster instead of a ball. But that may not amass the required amount you need, and the process of earning enough gems will still likely be a slow climb -- which can significantly delay unlocking new items and moving on in the game. Because building construction, food production, and even food placement can involve a waiting period, kids may find themselves wasting time unless they pay gems to accelerate things. The gameplay starts to seem pretty repetitive, and watching how slowly gems accumulate can be frustrating. It can start to feel like you have to buy additional packages of them from the in-app store to experience Supermarket Village - Farm Town in a decent timeframe -- or remain stuck doing busywork, which isn't very interesting for long.