This study explored the effects of adding visual continuous feedback in the form of feedback bars to a teachable-agent based learning game in mathematics. Forty-five (45) children, 8- to 12-years-old, from three Swedish school classes used the game during four math lessons. The focus was on how feedback to the students regarding their teachable agents learning progression – and different detailedness of such feedback – affects how the students (in a teacher role) experience the learning game. The results suggest that students were positive towards receiving immediate and continuous feedback, but their preferences with respect to the detailedness of the feedback differed according to their age. We found a divergence as to the preferred number of bars, where the 3^rd and 5^th graders preferred 1 or 3 bars but where the 2^nd graders preferred the more detailed version (6 bars) despite their lack of understanding of what the different bars represented.