Thank you for your email. Your daughter is not too young to learn about money and I applaud you for giving her the opportunity to do so.
Unfortunately, a place such as a tuck shop with many sweet temptations is not a good place to learn to budget. Instead of giving your daughter a weekly allowance rather give her a daily allowance. Sit with the tuck shop menu and discuss with her what she will eat each day teaching her to make healthy choices and why it is important; so our bodies can be healthy and our brain can learn well. Give her just enough money for each day and place it envelopes marked with the day of the week so it saves time in the mornings.
I would urge you to consider giving her homemade lunches rather than letting her buy from the tuck shop everyday as there are few tuck shops which stock good quality healthy foods that children need. She can help you prepare her lunches and you can teach her about healthy eating.
Some ideas for lunch boxes are: Fresh fruit and vegetables, nuts, raisins, dried fruits, homemade muffins, yoghurts and yogi sips, cheese, cold chicken and salads, left over supper,cereal bars, sandwiches with peanut butter, cheese, marmite, fish spread, hard boiled eggs, quiches, and wraps.
Let me know if you need further advice and let me know how you both are doing.