Celo

The Blockchain Attendance Registry is a secure, transparent, and tamper-proof on-chain attendance management system built using Solidity for EVM-compatible networks such as Ethereum, Polygon, and BNB Smart Chain. It allows institutions—such as universities, companies, and event organizers—to register participants and record attendance immutably on the blockchain. Every attendance action is logged as an on-chain event, creating a verifiable audit trail accessible to anyone.

Donation Tracker is an immutable and transparent donation-tracking system built on Ethereum. It lets anyone donate ETH to any wallet while permanently recording all donation history on-chain. Every transaction is timestamped, publicly visible, and stored forever, ensuring complete trust in the donation flow. GitHub Repository: https://github.com/bubbl3sss/Donation-Tracker

CoinToss is a simple blockchain-based wagering game built using Solidity. Players can wager ETH (or the native token on a network like CELO) on the outcome of a virtual coin toss — Heads or Tails. If they guess correctly, they win double their wager. If not, their wager stays in the contract. This project demonstrates how to: Accept and send Ether in Solidity. Use pseudo-randomness (for learning purposes). Manage ownership and withdrawals securely. https://github.com/pragati-shaw/web.sol.git

SafeProof is a beginner-friendly Solidity smart contract that brings product authenticity, ownership history, and warranty tracking to the blockchain. Manufacturers can register their products on-chain, while buyers can transfer ownership and verify warranty validity anytime — without relying on intermediaries. https://github.com/sumana067/SafeProof

Access to healthcare should be secure, transparent, and user-controlled. Our platform empowers individuals to fully own and manage their health information using decentralized technology. Each user receives an NFT that serves as a secure access key to their encrypted medical data, consultations, and verified hospital records. By combining decentralized storage, encryption, and NFT-based access, the platform ensures that health data is protected from unauthorized use while remaining easily…

Immutable Grade Ledger is a decentralized smart contract that allows educational institutions to record, verify, and publish student grades in an immutable and transparent way. Once a grade is entered, it cannot be altered or deleted, ensuring complete trust and authenticity in academic records. This project is ideal for learning Solidity, smart contract deployment, and blockchain-based credential verification. https://github.com/MdAbuHumza/CertiScore

MemoChain is a beginner-level Solidity smart contract built on the Celo testnet (Celo-Sepolia). The idea behind MemoChain is to create an on-chain card matching memory game, where players can flip and match pairs of cards stored directly on the blockchain. This project is meant to help newcomers to Solidity understand smart contract basics, events, and state management in a fun and interactive way. GitHub Repo : https://github.com/RanitPal/MemoChain

HalloApp allows users to deposit, withdraw, and track their Ether savings directly on the blockchain. Every transaction (deposit or withdrawal) is stored permanently on-chain with a timestamp — ensuring complete transparency and security. This project is designed for beginners learning Solidity and blockchain app development using the Celo network or EVM-compatible blockchains.

PrizeFi is designed as an educational blockchain project for learning how decentralized lotteries work. Participants can join by paying a small entry fee, and the contract randomly picks a winner who receives the entire prize pool. ⚠️ Note: The randomness in this demo uses block data and is not secure for real-world use. For true randomness, use Chainlink VRF or another oracle service. Github link : https://github.com/drishyam27/PrizeFi1.sol

A simple and transparent blockchain donation platform built with Solidity. GiveFi enables anyone to donate ETH to verified causes, while ensuring every transaction is recorded publicly on-chain. It is an educational blockchain project that demonstrates how smart contracts can be used to bring transparency to donations. It allows the contract owner to add verified NGOs or campaigns, and donors can send funds directly to these causes — no intermediaries, no hidden fees. All donations are stored…

ChainToss is a simple demo smart contract built in Solidity that simulates a coin flip game directly on-chain. Players send a fixed bet amount (0.01 ETH) and guess Heads or Tails. The contract then generates a pseudo-random result — if the player guesses correctly, they instantly win double their bet! This project serves as an educational example, ideal for beginners learning: Payable functions Events Randomness (and its limitations on-chain) ETH transfers and balance handling GitHub Link…

The TransparentLottery contract allows users to enter a lottery by sending a small amount of Ether (minimum 0.01 ETH). Once enough players have entered, the manager (the person who deployed the contract) can call a function to randomly select a winner, who automatically receives the entire prize pool. All interactions are recorded on-chain, making the process fully transparent and verifiable by anyone. https://github.com/Jay6949/Jayjit-2025.sol