Affinity offers a variety of account types to help members save money, because no single option is best for all personal finance needs and situations. Our SmartStart savings account is probably the best kids' savings account choice because they get 2.00% APY (annual percentage yield) from the first dollar they save, up to a $5,000 balance. We also have other accounts, such as MoreSavings, that offers tiered savings with higher rates for higher balances.