New Items after some levels

i would like first to appreciate the effort for merging gaming with teaching programing in the same time i have a question Why the rewarded New Items after the levels are kind of useless items , either they are so low level items or i already have them also i keep getting the same items all the time .

These items are " Rewards " so they should have value for the players

also if i played the same level again should i gain a different tool or i stuck with the one i got the first time i played the level

The reward for completing a level doesn’t change and you don’t get it again - you don’t gain additional items/gems for completing the same goal again unless the level a repeatable challenge with increasing difficulty. (No grinding)

The main reward in most levels is gems. Complete a number of levels and collect enough gems to buy items of value.

Check this for a list of items that you can get from levels: