This poor widow, from her poverty, has offered her whole livelihood. Jesus couldn’t have been possibly suggesting that the widow’s offering of two ‘small’ coins was more praiseworthy than that of the other contributors. If this is what he was suggesting, he was on the verge of losing the friendship of the Temple authorities (if there was any left). The Temple relied on the generosity of the wealthy for its daily operations. If praiseworthy offering would be reduced to two pennies or its equivalent, then the Temple as an institution was to find itself staring at an uncertain future. It has also been suggested that Jesus praised the widow because the wealthy people offered from the surplus of what they had as Jesus himself had pointed out. It is true the wealthy contributed from their surplus, but that shouldn’t make their offering non-praiseworthy. All the offerings made that day were praiseworthy. However, I tend to believe that Jesus singled out the poor widow because of the gesture she made: as Jesus remarked, she offered her ‘whole livelihood.’ 
The widow’s two coins was all she had. It was all she was living on. Her two coins couldn’t have compared much against what others were putting into the offering box. Her two coins would not have been missed had she chosen not to make her offering. But she didn’t let that prevent her from making her contribution. She chose to make the offering anyway. And this is because she understood that it was not how much she was putting into the box but rather  what her offering represented that counted. Hers was an offering from the heart. It meant a lot to her than to the Temple authorities or even to God. She was doing it for herself. She went back home feeling fulfilled and in gratitude for the opportunity to make an offering to God. She went back home feeling justified because she had fulfilled her obligation. And she did it without counting the cost. This is what an offering should be about. This is the teaching that Jesus wanted to pass across.